Hand Loading for Long Range 3: finding start OAL

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#1
Chapter 3: "Where’s my rilflings and where should I put them?"

So having prepped and primed our brass & sorted our bullets into identical lots now we need to know at what overall length we need to seat the bullet into the case. How do we figure that out?
Well there are a few ways to establish a great starting point, and after that during our load refinement the rifle will tell us what it wants- exactly what it wants.

So there are a number of ways of determining at what overall length (OAL) a loaded round’s bullet is engaging the riflings. I’m gonna cover my favorite. I feel it is the quickest and best way.


It is done by using a cleaning rod, a blunt patch jag and two rod stops. If your unfamiliar with rod stops, they are just that. Small round collars that clamp onto you rod to allow it only to go into the bore so far. This is normally used when stroking a bore with JB bore cleaner, ISSO paste, etc. so that the particular jag, brush or felt pellets your using to JB with do not pop out of the muzzle causing you to have to re-affix your JB/ISSO holder.

Rod stops at Brownells.com

There is a fine all stainless steel rig made for this purpose sold at Sinclair, but it is a good bit more expensive than simple & cheap cleaning rod stops.
Here they are...

Here's mine I'm referring to in this instructional:



Okay. First let’s wipe off the lugs on our bolt as well as the locking lugs of the action to ensure they are engaging bare metal to bare metal, without powder residue, grit or carbon pinned in between which would throw our measurement off by many thousandths. Make sure the bolt face is clean as well.

Close the bolt on an EMPTY chamber and to make this is an idiot proof operation let’s go ahead and put the trigger safety on. The following actions are easiest done by sitting the butt of the rifle on the floor with the weapon vertical. Bungee the barrel to the back of a chair or workbench (etc.) so it’s held in place. I in the past also have sat in a chair, placed the rifle butt on the floor and held the rifle vertical between my knees. Either needfully frees both hands to manipulate the rod and rod stops.

Now with the rod stops and blunt jag already on the cleaning rod go ahead and insert the cleaning rod into the muzzle end of the barrel and down the bore until the blunt jag is resting snugly against the bolt face.

Now we need to “zero out” our rod stops. We do this by holding the cleaning rod into the bore and snug against the bolt face. While holding there slide BOTH rod stops down snugly against the muzzle and tighten down the thumbscrews locking them in place. GAS GUNNER: pushing the rod against the bolt face you will feel it spring back a little then stop solidly. Make sure you have it pushed to a solid stop past the springiness.

Here's a picture of my stop's zero'd out on my rifle:




(What’s that you say? Sexy brake? Thanks I just made it this past week. It is my first ever and I thought it up, designed it and made it all while… well as i was making it! I tried it today. It works GREAT, but evidently it’s louder than the cries from hell. After I fired the first shot, everybody started backing away from the firing line! Great, they were a distraction anyway… : )

Now we need to take a resized, UNPRIMED (as in no primer) case, containing NO POWDER and seat a bullet long. Say .200” longer than book spec for the bullet you are using. Take this dummy round and gently slide it into the chamber. Bring the bolt up VERY gently behind it until you just feel the bullet touch the riflings in the bore. Now take a good rubber band and loop it over the scope and onto the back of the bolt to hold it in a forward position.

This insertion of the dummy round needs a gentle touch with both your hands, and in the holding of the bolt by the rubber band.. With the keen angle of the bullets ogive and the gentle angle of the lead-in on the rifling it is EASY to jam the bullet on deeper into the riflings and not know it.

Avoid doing this, but no need to have worrisome sweat bead up on your forehead. If you do jam it in an extra couple of thousandths it’s not the end of the world. We are only trying to find a good estimation here. We are going to refine this overall cartridge length as the LAST step in our load work-up. We just need a good start point for now.




GAS GUNNERS: your buffer spring serves as your rubber band. Point the weapon muzzle down. Drop the dummy round gently into the chamber. Now SLOWLY & GENTLY ease the bolt forward until it just touches the back of the dummy round. Gently ease your hand off the charging handle smoothly transferring the holding power to the buffer spring.

Now again with the weapon fixed in a vertical position slide the cleaning rod back down the bore until the blunt jag delicately comes to rest on the meplat of the bullet. Now loosen and slide the lower stop (the one already closest to the muzzle) down until it’s snug against the muzzle and tighten the thumb screw.



Remove the cleaning rod from the bore being careful not to bump the stops out of position. Take your calipers and measure the distance BETWEEN the rod stops.




Write down that measurement. Now repeat the whole process two more times (so long as your not getting greatly differing measurements. If your getting more than a few thousandths difference between each measurement something is wrong and you'll not end up with good data.) and average all three. VIOLIN! You have the measurement for the cartridge overall length at which that bullet is just lightly touching the rilfings. Well done!

Now this is all well & good, but there is one critical thing you need to remember that we learned from Chapter 2: not all meplats are the same! This measurement is only good for THIS ONE PARTICULAR BULLET. Because we measured from IT'S MEPLAT, and seldom do two bullets have the same meplat squareness and length (microscopically speaking.)

So what do we do? We record the measurement off the ogive, which is the same from bullet to bullet and use that figure from now on. How do we do that? Slow down- I’m getting there.

Now take the dummy round that you did the Rod/Stops work with and place it in the loading press. Thread in your seating die to the lock ring as per normal. Back your seating stem or micrometer WAY WAY out. Now raise the dummy round up into the die all the way. While holding sufficient pressure on the press handle, begin screwing down the seating stem until you feel it touch the bullet.

Now raise the press handle removing the dummy round from the die. Screw in the stem just a little and raise the dummy again & seat the bullet to that depth the stem is currently at.

Now take the dummy round out and measure it, case head to meplat.



Continue this seating the bullet in the case a little more each time until you get it to the exact length you came up with from the cleaning rod stops routine. Now we’ll get that ogive measurement your jumping up & down for.

So get out your calipers, comparator body & the proper insert you that learned about in Chapters 1 & 2. This time you’ll only need one body (holder) and one caliber appropriate insert. Now open the jaws and attach the comparator assembly to one of the jaws.


Now measure the dummy round we have set up to our case-head-to-meplat over all length. The comparator however measures off the ogive instead of the meplat. We CAN use this measurement bullet to bullet to bullet for this particular bullet make, weight and style we are working with and it will maintain good consistency. (210 VLD depicted here.)


[ADDENDUM: if you shoot a lot to the tune of eventually shooting out and having to replace barrels, or your won over to my camp of trying to make your handloads as perfect as you can- SAVE THIS DUMMY ROUND. Label it, and put it in a safe place ot be used later.

As you shoot your rifle, the very start edge of the rifling will be eroded back from the "blow torch effect" of the hot gases coming from the mouth of the case as well as a piece of metal, aka "bullet" slamming into them time after time. This to explain that the very beginning of your rifling slowly moves towards the muzzle as it is eroded/worn away.

If your serious about accuracy- thought you have found THE perfect load you will have to "chase the rifling" as it's called. Say you found your rifle shoots amazing with a certain load and the bullet .008" jammed into the riflings. Well after a lot of rounds in a non-barrel burner cartridge, or some in a known barrel burner, though you load the OAL of the round the same it will not be the same in the end because the riflings are actually moving on you!

Hence as the barrel wears your your .008" jam is actually now only .004. then it's only .001 months later it is actually .003 JUMP. So to maintain that original .008" jam you'll have to keep actually loading you ammo longer and longer as you "chase(the wearing away of)the riflings." Periodically come back and repeat this initial OAL test to see where the start of the rifling is NOW, and you can again maintain that perfect .008 jammed in bullet to rifling relation you found in your load development.]


Lastly- one final note and word of caution. Now that we know at what measurement OFF THE OGIVE our bullet –touches- the riflings, we will start our load development .010” jammed into the riflings. That is .010” LONGER than the dimension we figured up through this described process. That number was just touching the riflings. Most rifles like to be about .010” in (“Jammed”) This is the OAL we will start our powder make & charge test’s with. (Next chapter.)

However <span style="color: #FF0000"><span style="text-decoration: underline"><span style="font-weight: bold">it is IMPERATIVE you understand the foll</span>owi</span>ng.</span> On occasion the rifle will prefer a different bullet/rifling relation. Perhaps it be .015” jammed, or .030” out of the rifling totally or .030” “jump.” But START ALL LOAD WORK JAMMED! This is because in the next chapter we are going to learn what actual MAX load for this rifle is with a given powder and this bullet. Being jammed into the riflings increases pressure! So as long as we learn our max powder charge while jammed, we are okay. HOWEVER, if we were to (think we) learn(ed) what max charge was without our bullet jammed and then jam it into the riflings, coupled with a max powder charge in search of a most accurate bullet setting we could blow up our rifle, loose both our eyes, our hearing a good portion of our face and destroy the rifle- that is if we come out of it alive. That all sounds scary, which is a good thing.

But so long as you START JAMMED and work towards JUMP your safe as can be. NEVER start jumping and move towards jammed when near or at MAX loads, no,no, no.

Well that covers determining where the bullet is in relation to the rifling and getting a good .010” jammed starting point. Next chapter is on experimenting with powders and charges.

-----------------------------------------------------------------------
This instructional took considerable time & effort. It is presented here for free. Enjoy! However if any one feels motivated to express appreciation a donation can be sent to the paypal account nativemant@yahoo.com. No big deal. Thanks! TresMon


 
Likes: DarinC
Feb 18, 2006
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Florida
#2
Re: Hand Loading for Long Range 3: finding start OAL

Great write up. Can't wait till the next one!

By the way, do you shoot F-Class at Oak Ridge? (ORSA)
 

chawk

Sergeant
Apr 10, 2009
279
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Eastern Shore, MD
#3
Re: Hand Loading for Long Range 3: finding start OAL

TresMon,

Another great write-up. I have really enjoyed reading all three of them so far and look forward to those to come. I appreciate your work!
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#4
Re: Hand Loading for Long Range 3: finding start OAL

Sail,
Yep, thats where I shoot 600 & 1000. Thanks for the kind words.

Chawk,
Thanks so much for the boost! I appreciate fok speaking up.

happy to help,
Tres
 
#7
Re: Hand Loading for Long Range 3: finding start OAL

I've been greatly enjoying these write-ups. Lots of great info.

But we need something similar for the guys who aren't so anal about every small detail being absolutely perfect. You know, the guys who aren't going to sort by bullet weight/length/roundness and those of us who aren't going to go buy loads of specialized gear meant for constructing the perfect round.

For many of us, "very, very good" is better than "perfect."

Thanks for the info, as it's good stuff.
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#8
Re: Hand Loading for Long Range 3: finding start OAL


I'm uncertain how less than your best can be better than your best, but the pages in the front of any reloading manual will provide you the information you seek.

"very, very good" is relative as well.

your happy I'm happy!
Tres
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#9
Re: Hand Loading for Long Range 3: finding start OAL


Note: I added an addendum to the original article at the top.
Regarding: [example]
About 3 weeks ago I began load development on a new to me 300 win mag. Since that time- the riflings have moved on me .008"
 
#10
Re: Hand Loading for Long Range 3: finding start OAL

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TresMon</div><div class="ubbcode-body">
I'm uncertain how less than your best can be better than your best, but the pages in the front of any reloading manual will provide you the information you seek.

"very, very good" is relative as well.

your happy I'm happy!
Tres </div></div>

For some of us, the perfection gained by going through <span style="font-style: italic">all</span> of these various steps is not worth the accuracy gained (I.e., for some, we will see diminishing returns if we go through all of the effort as not all of us are concerned with winning competitions). For some, the extra steps (and time and money) are not worth the extra gained in groups.

That's not to say that perfect ammunition shouldn't be strived for by those who need/desire perfect ammunition.

Many of us don't need perfect ammunition, but yet want to still strive for something that meets our needs (the middle ground between making basic ammo, what most manuals describe in the opening pages, and making perfect ammo).
 
Mar 23, 2009
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kentucky
#14
Re: Hand Loading for Long Range 3: finding start OAL

At first I seated a bullet long and jammed it home with the bolt. I made that measurement and loaded based on it. Did not trust that measurement so I bought a Frankford Arsenal Cartridge Overall Length gauge http://www.midwayusa.com/viewProduct/?productNumber=190644
I found a measurement 0.050 from what I was useing with the long seated bullet jammed into the lands. In the back of my mind I kept doubting those numbers.
So I bought a Hornady Lock-N-Load Overall Length Gage Bolt Action and found that the long seated bullet was .002 differant than the lock-n-load measurement. That was because I was jamming the bullet into the lands. It took 6 months and countless bullets downrange to figure it out. The Frankland rod stops are plactic junk. they flex and give false readings. Anyone want them?

I Love your reloading manual but in my experance The lock-n-load or a bullet seated long and driven in with the bolt is more accurate.

I find the Lock-n-load FAST and ACCURATE with no rod going down the tube or rubber bands...

I have no experance with the Rod stops from Brownells.com but I did try Frankford's junk which gave fasle readings puting me 0.100 off the lands when I was shooting for 0.050 because I shoot TSX.

I also found with this measurement changes with differant boxes of bullets or for TSX anyways...

eleaf I found that reloading manuals were way way off. So I beleave this is VERY important!

Keep the write ups comeing I learn something with each one! How many hours does it take to write one?

 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#15
Re: Hand Loading for Long Range 3: finding start OAL


Lovetsx,
By the time the pics are taken, uploaded to the net, the text posted, the pictures put it, arranged, rearranged I have had well over 4 hours +++ in one of these chapters.

My rod stops came from Brownell's. They are "opossum hollow" brand which is Sinclair. I normally get within .000- .002" reading when I do it the rod way several times so it's by far repeatable enough for getting an initial start length in my opinion.

Yes sir- different lots of ALL kinds of reloading components will vary. Primers, powder- bullets generally speaking no two lots are EXACTLY the same...
 
Feb 26, 2010
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Ohio
#16
Re: Hand Loading for Long Range 3: finding start OAL

Very informative TresMon. I have just been trying to determine my starting oal on my trg 42 in .300 win mag. I used the split case neck method on an empty round and my desired bullet. Chambered 8 times with the bullet slightly started into the case neck each time. Added the measurements for a total and then divided by 8. My product avg. oal was 3.55331 inches. This was with my planned plinking bullet: Hornady A-max/155 gr. I used this method due to not having a bullet comparator yet. Now I completely closed my bolt. No slamming it home. I was very gentle closing and opening and had better than 50% repeatability in my measurements and my extreme spread was .008 of an inch between my smallest measurement to my largest. I am sure I had some rifling crush as you mentioned because my bolt was completely closed. Now should I start here with my min. load and work up?, or should I add .010? My plan was to start @ the 3.553 oal. I enjoyed your write up, very well thought out!
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#17
Re: Hand Loading for Long Range 3: finding start OAL


Start + .010" jammed in from the measurement you found with the split case.. Stick with that until you find your powder & charge. Then refine your bullet seating depth.

PS- a 155 (??!!!!??) in a 300WM? (thats a bullet for the little .308 winchester) If your happy I'm happy- but to me a win mag is not even justified unless shooting 200++ grain bullets. Why short yourself of SO MUCH BC (aerodynamicy) when you got ALL THAT HORSEPOWER of tap?? Just food for thought.
 
Feb 26, 2010
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Ohio
#18
Re: Hand Loading for Long Range 3: finding start OAL

LOL! No shorting myself. Those are my bullets for my .308 win. I am placing an order this month for my gsc bullets hv and sp. Looking for that drive band benefit I've been hearing about I have just got to see for myself what they can do. The bergers have always been good to me in my .17 rem and the price has been tolerable. I personally was looking at the 190 gr vld from them for the 300 win mag also. Do you have experience with the 190 gr vld by chance. I spoke with a very experienced fellow today at the range, whom I'll just refer to as "Mr. Whisper". He informed me that over the years he has had good consistency with the heavier smk's. Barnes has a pair of offerings I will try in time. Oh if the money tree would just bloom. I did put the trg on paper for the fist time today at the range. Very disappointed in rem. ammo. Primers of nickel and brass clad mixed within the same box? Come on! The groups reflected as well. The federals on the other hand printed under an inch @ 100 yds. Had some two shot ragged holers with a third slightly out. Probably the nut learning the trigger. These were the 180 gr. el cheapo's as well. Next time back will be with some more break in rounds until the rest of the reloading fodder comes in. Thanks for the good info and I will be chasing the high bc's soon.
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#19
Re: Hand Loading for Long Range 3: finding start OAL

I have not tried 190's in my win mag. The debate there is 1. high velocity (with 190's) vs. 2. high BC with more weight to resist the wind. I figured since I opted for magnum recoil, go with the big pills! Plus I have found a place I am invited to to shoot 1500 yds. and the 210s do better out there...

And I know some guys shooting 190s in a .308... I figured I wanted to be in magnum territory...
 

lvmike

Sergeant
Mar 6, 2009
300
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LV, NV
#20
Re: Hand Loading for Long Range 3: finding start O

Correct me if I'm wrong (it happens alot), but shouldn't the thickness of the 2nd stop be measured and added to the measurement between the stops? See my pic for an easy explanation... The lengths of everything are arbitrary but the drawiings are all scale to each other.


edit: durr, I goofed on the length on the bottom drawing. it should be 2.750" not 2.435"
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#21
Re: Hand Loading for Long Range 3: finding start O


If you have BOTH stops on the rod and "ZERO" both stops on the muzzle with a BLUNT jag against the bolt face (all per my instructions) then you have ZERO distance between the stops.

Then with the bullet in the barrel....your moving the bottom stop/stop c distance BETWEEN the stops to the spread between the boltface & the meplat.

So then you merely measure the distance BETWEEN the stops.

In your drawing, had the top illustration shown two stops against the muzzle it would have been consistent with how I expressed it in my instructions. If we were to do it as you have depicted yes we would have to add because with your way we loose the solid zero point and go to a floating zero point reference.


 

lvmike

Sergeant
Mar 6, 2009
300
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16
34
LV, NV
#22
Re: Hand Loading for Long Range 3: finding start O

Ahh, I missed that in your instructions. That makes sence now, both stops slide on and you lock the farthest from the muzzle to set distance to bolt face. Insert the round, reinsert the rod, and lock the second rod stop.

Thanks for the help
 
Apr 16, 2009
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New Orleans
#24
Re: Hand Loading for Long Range 3: finding start O

I purchased the recommended setup from Sinclair's, so I'm going in from the bolt end. My measurement seems a little long. Any idea what ballpark a .308 700P should be in?
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#25
Re: Hand Loading for Long Range 3: finding start O


A little long does not surprise me. Shortish would get a raised eyebrow from me. Sorry I can't provide you with feedback on a 700P but I'm sure others will chime in.
 
Oct 28, 2008
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Colorado
#26
Re: Hand Loading for Long Range 3: finding start O

My OAL from case head to ogive is 2.124" in my 700 LTR in 308. I derived this from following TresMon's procedure.
 

Hellbender

Gunny Sergeant
Apr 23, 2008
1,111
1
36
50
Lebanon, Missouri
#27
Re: Hand Loading for Long Range 3: finding start O

Stock Remington .308 chambers normally have a lot of freebore.

My 5R has .195" (no that's not a typo) w/ a 178 A-max at mag length.

But it shoots in the mid .2's consistantly (bedded in new stock with good trigger).

I don't understand how......
 
Oct 28, 2008
273
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Colorado
#28
Re: Hand Loading for Long Range 3: finding start O

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Hellbender</div><div class="ubbcode-body">Stock Remington .308 chambers normally have a lot of freebore.

My 5R has .195" (no that's not a typo) w/ a 178 A-max at mag length.

But it shoots in the mid .2's consistantly (bedded in new stock with good trigger).

I don't understand how...... </div></div>

.195" of freebore?
 
Oct 28, 2008
273
0
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Colorado
#30
Re: Hand Loading for Long Range 3: finding start O

Strange. From case head to rifling is 2.124" in my LTR with 1549 rounds through it. I just compared the measurement from case head to ogive in a SAAMI spec'd 2.810" OAL cartridge to a reference cartridge I made from my LTR head space and the difference was .053". It sounds like someone did some "extra" chamber reaming on your stick. Glad it shoots well.

Edit: I was looking in my 2nd edition Sierra reloading manual (circa 1978) and they have the OAL for the 308 at 2.800; the Nosler #4 (circa 1996) has it at 2.810 as I originally thought it was supposed to be.
 

Hellbender

Gunny Sergeant
Apr 23, 2008
1,111
1
36
50
Lebanon, Missouri
#31
Re: Hand Loading for Long Range 3: finding start O

I bought the rifle NIB, and it has about 750 rounds through it now.

I was flabbergasted when I checked it, but got checking around, and this is pretty common on the 5R (at least at the time I got it about 1.5 years ago).

Figured I'd shoot it a bit, and it was a tackdriver from the first shots. I can run the 178's about 2720 fps without pressure signs, which is about 120+ fps too fast, so maybe Roy Weatherby was on to something all those years ago.

I won the PMC II (at Hard Rock) match with it in Alabama last year.
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#32
Re: Hand Loading for Long Range 3: finding start O



Hey, dont sweat a long throat, just chase the riflings and keep shooting it till the barrel goes south!
 

Hellbender

Gunny Sergeant
Apr 23, 2008
1,111
1
36
50
Lebanon, Missouri
#33
Re: Hand Loading for Long Range 3: finding start O

How can you chase rifling when a new gun STARTS out 1/4" from the rifling loaded to mag length?

A rhetorical question obviously, but how can it shoot in the mid .2's consistently, while jumping almost .200" with the rounds loaded to 2.94" OAL, it makes me wonder about how critical jamming bullets into the lands really is, as I have been taught to do for 30+ years of reloading, as the only way to load REALLY accurate ammo. Maybe this gun is a fluke, but it makes me want to experiment with very long throat length....

BTW, TresMon, thanks for the excellent articles and all the time and effort you have put into these! It is appreciated!
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#34
Re: Hand Loading for Long Range 3: finding start O

HellB,

Often you have a choice between being at the riflings, OR mag feeding, not both.

Yes, some rifles & bullet get a long greatly with significant jump.
Weatherby chamberings ALL have a BUNCH of free bore, it is part of the design...

Read bergers tech article on VLD bullets and OAL... I cut and pasted it below...

Thanks for your kind words,
T

""VLD Bullet Design
The VLD (Very Low Drag) bullet design was born from a request made by the US 300 Meter Shooting Team. It was determined that they were dropping points late in the matches due to recoil fatigue. Bill Davis and Dr. Lou Palmisano were asked to design a bullet and case combination that shot flatter than the 308 case and 168 gr bullets the team was using at the time. After a design was created Walt Berger was approached to make the bullet. The 6mm 105 gr VLD was born and shot by the US 300 Meter Shooting Team using a 2” PPC (modified 220 Swift). This combination shot with less felt recoil and a flatter trajectory than the 308 case using the 168 gr bullet and higher scores were the end result. This successful bullet design soon found its way into all long range target competition and the VLD shape spread into all other calibers.
The VLD bullet design is a combination of two very specific features. The first is a boat tail which is common on long and heavy bullets. The second and most important design feature is the long secant ogive. It is this ogive shape that allows the bullet to experience less drag as it flies to the target. This reduced drag is how the VLD shoots flatter and is less affected by wind (less drift) than other bullets. Reduced drag also translates into higher retained velocity. These are important results if you want your bullet to help improve your accuracy by requiring less sight adjustments when conditions change.
For years we have relayed that it is best to jam the VLD into the lands for best performance. This works for many rifles however there are many rifles that do not shoot the VLD well when the bullet is jammed. We have learned that the VLD can shoot best as much as .150 jump off the rifling. VLD bullets can be sensitive to seating depth and it has been found that these bullets shoot best in a COAL “sweet spot”. This sweet spot is a COAL range that is usually .030 to .040 wide.
The quickest way to find this sweet spot is to load ammo at four different COAL. Start with a COAL that allows the bullet to touch the rifling. The next COAL needs to be .040 off the lands. The third COAL needs to be .080 off the lands. The last COAL needs to be .120 off the lands. One of these COAL will outperform the other three by a considerable margin. It has been reported that the VLD bullets don’t group as well at 100 yards but get better as the bullet “goes to sleep” at further ranges. We have learned that by doing the four COAL test you will find a COAL where the VLD bullets will group well at 100 yards. Once the COAL that shoots best is established you can tweak +/- .005 or .010 to increase precision or you can adjust powder charges and other load variables. Frankly, those who do the four COAL test usually are happy with the results they get from this test alone. "" {Quote came from here}
 
Oct 15, 2006
233
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alaska
#36
Re: Hand Loading for Long Range 3: finding start OAL

Tresmon great stuff its true you can teach a old dog new tricks! Any luck finding a job in a setting you like we have a great trooper school here in Alaska they are always looking for good guys . Dont know if it is what your after also they have a great intern program with the state for summer jobs fish counting,counting geese and seeing how fast lead shot drops in one said plot of tundra I thought you might like the last one I think they are doing it with steel shot now I have did a fair amount of shot shell reloading the last 30 years do you load them as well? regards and keep up the writing I never miss a post of yours Kim
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#37
Re: Hand Loading for Long Range 3: finding start OAL

Kim,

Thanks for your kind words. Yes I would be interested in any of the above jobs. PM sent.

[your PM box is maxed out, I can't send you a message. shoot me a pm or e-mail. I'd like more details about the work.]

Much appreciation,
Tres
 
Sep 16, 2008
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Boston, MA
#40
Re: Hand Loading for Long Range 3: finding start OAL

I've always just used a bullet in a FIRED case and then just measured to where the rifling sets the bullet back. It seems like using the rod and rod stops is just an extra, unnecessary step. A fired case has a loose enough neck that the bullet should slide quite easily, and done a few different times with similar readings gives me enough confidence. I understand that the ogive to land angle is shallow enough that it might not be completely precise, but how much extra accuracy are you actually getting using the cleaning rod in addition?
 

TresMon

Gunny Sergeant
Dec 3, 2007
1,158
26
48
NW USA
#41
Re: Hand Loading for Long Range 3: finding start OAL



TT, if your happy I'm happy. However it's quite easy for the bullet to stick in the riflings on any "set back" method. I don't count on it being actual, even if you get "consistent" reading. How do you know your not getting consistent bullet set back & pull out?

If your getting great results down range, Go for it!
Tres
 
Sep 16, 2008
143
0
0
35
Boston, MA
#42
Re: Hand Loading for Long Range 3: finding start OAL

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: TresMon</div><div class="ubbcode-body">

TT, if your happy I'm happy. However it's quite easy for the bullet to stick in the riflings on any "set back" method. I don't count on it being actual, even if you get "consistent" reading. How do you know your not getting consistent bullet set back & pull out?

If your getting great results down range, Go for it!
Tres</div></div>

Yea thats what I figured. I usually run at least .02" jump and work up loads from there, so I'm not too concerned about accidentally jamming it into the lands on a round. Accuracy is quite good nonetheless, and certainly good enough for my needs!
 
Oct 31, 2006
263
7
18
AUSTRALIA
#45
Re: Hand Loading for Long Range 3: finding start OAL

I have been using this method for a while now.

1. Seat projectile long, chambering and then measuring with the Sinclair Comparator.
2. Setup up seating die to this length, and then by using a little trial and error, slowly reduce the seating depth in small increments and chambering, each time using fine steelwool to remove the land marks (just polishes them off).
3. I keep reducing the OAL until you cant see any land marks on the projectile. You can work out pretty darn closely when the projectile first touches the lands.

After you do it a couple of times you can have a educated guess and it speeds thing up greatly. I usually just go 20thou in from the first contact!!

Hope it makes sense!!

Cheers
 
Oct 12, 2010
100
0
0
29
California
#50
Re: Hand Loading for Long Range 3: finding start O

So I drew a picture so that it's easier to understand what I'm asking.



So if I use bullet A to find max COL when the ogive touches the lands, then do I use this same COL @ the ogive for bullets B and C? Or do I have to retake this measurement for each bullet?
 
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