300 PRC update

Rocketmandb

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Never seen a carbon mark like that
It does look kind of odd. If doctor hadn't said it was a carbon mark, I would have said that something is wrong with the brass. If you look closely at the edges of carbon marks, they tend to be diffuse, as they are made by gas. These marks have very defined edges - I don't see how the finger-like markings in the first image could have been made by gas. I would suggest sending a picture to Hornady and asking them how these marks could have been made.
 

doctordoctor

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It does look kind of odd. If doctor hadn't said it was a carbon mark, I would have said that something is wrong with the brass. If you look closely at the edges of carbon marks, they tend to be diffuse, as they are made by gas. These marks have very defined edges - I don't see how the finger-like markings in the first image could have been made by gas. I would suggest sending a picture to Hornady and asking them how these marks could have been made.
The gas marks are consistent on every fired brass that I have out of my gun. Something is wrong.
 

Rocketmandb

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The gas marks are consistent on every fired brass that I have out of my gun. Something is wrong.
For a gas to make hard edges like that, the unmarked portion has to be completely sealed. Conceivably, the brass could be expanding and sealing against the chamber before the round exits, but I wouldn't think you'd get those sort of irregularly shaped lines. Do any two pieces of brass have the same or similar patterns?
 

doctordoctor

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For a gas to make hard edges like that, the unmarked portion has to be completely sealed. Conceivably, the brass could be expanding and sealing against the chamber before the round exits, but I wouldn't think you'd get those sort of irregularly shaped lines. Do any two pieces of brass have the same or similar patterns?
All the brass has those findings. I should and will check concentricity. I'm guessing something is off with the chamber
 

jetmd

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I would index 4 rounds with a witness mark, single round feed with said mark into the position of 12, 3, 6 & 9 O'clock.

When fired does the carbon mark always end up in the same spot relative to the chamber? Or does it follow the
concentricity of the brass?

On my larger caliber rifles I anneal after each firing. It will not hurt your brass if done properly and it keeps
the neck/shoulder area flexible allowing the case to expand during the firing cycle which helps with several
issues.....neck tension, sealing the chamber etc. Although this is not a cure if the neck of the loaded round is way too
small vs. chamber neck size.

I hope this makes sense? It did when my little brain typed it out :(

Respectfully submitted,

Chet
 

DAVETOOLEY

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So what's my options? Just deal with it and move on?
I recommend to my customers to always start with new brass. The reason is 99.9% of the time, if there is a problem it's traced to the brass that's been fired in a different chamber. Not all reamers are the same size, close but there are -0.000" + tolerances. Then the chamber. Not everyone cuts the same size chamber even using the same reamer.
 

scottchevelle

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Earlier someone posted they were having trouble finding RL25. I found some at Bass Pro shops in Auburn Hills, MI. Bought one but they have a couple left.
 

b2lee

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Powder Valley is showing 14 5lb jugs and 21 llb bottles in stock at the moment. Yesterday their rebates started. Buy over 4lbs of Alliant and get $2 a pound rebate...up to $20.
 

b2lee

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I got plenty of powder, a few hundred 225 ELD-M's, match die set, but I may have to go sit on the I-75 off ramp with a sign that says %$$ for BRASS if the shortage goes on much longer.

I did get in 40 rounds of 225 ELD-Match ammo today... necks measured .3375....so with spring back, it looks like I'll have about 2.5 thou of neck tension with my 334 bushing when I go to reload them.

Now the only thing I'm missing is....wait...my rifle :)
 
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snipersteve

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Does anyone know if the newish Magpul 700 Pro LA chassis will accommodate 300PRC and if so, what mags would you have to use? The LA PMAGS only allow for 3.5" long projectiles.
 

jwknutson17

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Does anyone know if the newish Magpul 700 Pro LA chassis will accommodate 300PRC and if so, what mags would you have to use? The LA PMAGS only allow for 3.5" long projectiles.
That would be nice... But unless Magpul comes out with CIP mags I am going to say.. doubt it. I don't think they would make a chassis that didn't use their own LA magazines. But I could be wrong.
 

b2lee

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Does anyone know if the newish Magpul 700 Pro LA chassis will accommodate 300PRC and if so, what mags would you have to use? The LA PMAGS only allow for 3.5" long projectiles.
The 225 ELD-M loaded cartridge I'm fondling in my hands right now measures 3.674. I plan to load them longer. Going to run an AICS CIP mag that allows up to 3.745 OAL.
 

jwknutson17

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The 225 ELD-M loaded cartridge I'm fondling in my hands right now measures 3.674. I plan to load them longer. Going to run an AICS CIP mag that allows up to 3.745 OAL.
Correct. But I think he was asking if that Chassis would take CIP mags instead of the Magpuls that are too short for the 300 PRC rounds.
 

snipersteve

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That would be nice... But unless Magpul comes out with CIP mags I am going to say.. doubt it. I don't think they would make a chassis that didn't use their own LA magazines. But I could be wrong.
The website says the chassis will take "Magnum - AICS Long Action magazines". Obviously along with their own PMAGS. Is the AICS mag they mention one that can handle 300PRC?
 

jwknutson17

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The website says the chassis will take "Magnum - AICS Long Action magazines". Obviously along with their own PMAGS. Is the AICS mag they mention one that can handle 300PRC?
I would call magpul. There are at least 3 different length of AICS mag magazines. 3.615, 3.675, and 3.750 are the ones that come to mind.
 
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b2lee

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Might be worth a call to them...but I'm willing to bet that they are talking about the AICS 338 Mag that has an OAL of 3.625 max.
 
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snipersteve

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Correct. But I think he was asking if that Chassis would take CIP mags instead of the Magpuls that are too short for the 300 PRC rounds.
It looks like AICS makes a 300WM magazine and a 338LM magazine. The 338 is the CIP and fits the description above or the 300WM version? I can't find specs online. Which is annoying.. But it sounds like the Magpul chassis takes the 300WM mags but I'm not sure if 300PRC fits in those mags because I don't know the internal dimensions...
 

snipersteve

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I would call magpul. There are at least 3 different length of AICS mag magazines. 3.615, 3.675, and 3.750 are the ones that come to mind.
If one of them doesn't fit these dorks just created a really cool new chassis that doesn't fit the hottest new 30 cal cartridge! Fingers crossed. I'll post if I get an answer..
 

snipersteve

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I would call magpul. There are at least 3 different length of AICS mag magazines. 3.615, 3.675, and 3.750 are the ones that come to mind.
Magpul says the max dimensions of their magwell is 3.72". So that means the largest AI mag that would work is the intermediate? Or is the conversation in earlier threads about modifying mags taking the 3.750's and shaving them down?
 

jwknutson17

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If one of them doesn't fit these dorks just created a really cool new chassis that doesn't fit the hottest new 30 cal cartridge! Fingers crossed. I'll post if I get an answer..
The magpuls footprint are the same as the 3.715 mags that allow COAL of 3.615. As the polymer is thicker then the metal mags, the magpuls have shorter COAL allowance. So their chasiss technically would need to accept as least the 3.775 mags with 3.675 to accept the shorter 212eldx offering. If you wanted to shoot the factory 225s, the chassis would need to accept the 3.850 mags that have a coal of 3.750.
 

jwknutson17

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Magpul says the max dimensions of their magwell is 3.72". So that means the largest AI mag that would work is the intermediate? Or is the conversation in earlier threads about modifying mags taking the 3.750's and shaving them down?
You are stuck with the 3.715 mags that only allow 3.615 COAL.
 

jwknutson17

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ITEM
Cartridge
CAP
W
L
H
MAX OAL
00100-0048*
.300 WM​
SSSF
3RD​
.736​
3.715​
2.93​
3.615​
00100-0049*
.300 WM​
SSSF
3RD​
.736​
3.775​
2.93​
3.675​
00100-0050​
.300 WM​
SSSF
3RD​
.736​
3.850​
2.93​
3.750​
00100-
0001​
.300 WM​
SSSF
5RD​
.736​
3.715​
4.01​
3.615​
00100-
0004​
.300 WM​
SSSF
5RD​
.736​
3.775​
4.01​
3.675​
00100-
0023​
.300 WM​
SSSF
5RD​
.736​
3.850​
4.01​
3.750​


Look at the Length of the mags. If magpul says 3.72. The only mag that will work is the 3.715. And then look the MAX OAL. This is from Accurate-Mags site
 

snipersteve

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The magpuls footprint are the same as the 3.715 mags that allow COAL of 3.615. As the polymer is thicker then the metal mags, the magpuls have shorter COAL allowance. So their chasiss technically would need to accept as least the 3.775 mags with 3.675 to accept the shorter 212eldx offering. If you wanted to shoot the factory 225s, the chassis would need to accept the 3.850 mags that have a coal of 3.750.
Poop. I'm only interested in Match ammo for a target rifle. Too bad this isn't for an elk gun. I'd be golden. Thanks for the .02.
 
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senna.bra

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Took the AXMC w new 28” 1-9 barrel I found online while I wait on my 2nd blank. 1050 yards with 2mph to 4mph wind. I did take it to 1,100 too with better conditions and it was a hammer. “Disclaimer”, I am still learning to read the wind...

This is factory hornady 225gr load load and SD was around 8ish.

1050 yards
1,100 yards
 

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jwknutson17

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Spoke to Sarah at Redding this morning about 300 PRC dies. They said they have the "Custom" 300prc type S FL bushing dies being made right now. She said 3-4 weeks and directed me to Accurate Guns and Ammo for the order. Placed the order this Morning and should have it in a month. Angel was a pleasure to work with there and anyone looking for that specific die should give her a call. I was not going to mess around with the Hornady dies any longer and ordered one I know that will just work. FYI for anyone looking to get on that batch that's coming out.
 

senna.bra

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I am a fan boy of the Berger 230gr OTM.

Loaded H1000 and 230grs 0,020 jump. Using regular rifle Federal primers.

75.9gr H1000 2849 FPS SD9.4
76.2gr H1000 2859 FPS SD 5 “some pressure”
76.5gr H1000 2875FPS SD 7.8 “pressure”

5 shot lots, all three were one big hole at 100 yards.

1.9 twist 28” barrel

I am here to tell you that the Hornady Factory loaf ain’t with H1000 for what I can tell.

I am getting 2930 FPS with Hornady 225gr ELD with NO pressure at all.
 

dntworry

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I currently have a 300WM but it has a CF barrel and is more geared as a big game hunting rifle. Debating between 300 PRC and 338 Lapua AI for an ELR rifle. What kind of velocity do you guys think this thing will push 198gr Flatlines?
 

wspe1

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I see a lot of different barrel lengths and types being talked about on this thread. I was considering a 28 in bartlein barrel now I am thinking a 29 or 30. Also I need to determine which contour. I was considering the varmint contour, but I am wondering if this might be way to big for a 29 or 30 in barrel. Any recommendations on barrel set ups? And what is the final consensus on barrel twist?
 

Polizei45

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The barrel I have for my 300 PRC project is a Bartlein Heavy Palma 30". I think I'm going have it cut to a 28". It will be 30" with the Holland Radial Baffle muzzle brake. If I go much longer I don't think it will fit in my safe.
 

b2lee

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The barrel I have for my 300 PRC project is a Bartlein Heavy Palma 30". I think I'm going have it cut to a 28". It will be 30" with the Holland Radial Baffle muzzle brake. If I go much longer I don't think it will fit in my safe.
My project is also using a Barlein but with the #9 Heavy Varmit. Once the smith takes that blank and faces off each end and chambers and threads it....we are looking at a 28" barrel...you can get extra length from Barlein at a mere $10 an extra inch...which is cheap as can be...but the problem is the wait times for non-standard lengths. Once I put the APA Lil'B on it...it will come out around 30"

The twist is 1-9. ...which is just going down the middle between the discussion of the 1-10 crowd and the 1-8 guys.

Loaded rounds = 200....Rounds sent down range = 0 I'm still months away from pulling the trigger :(
 

Dippy

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Went with a Bartlein 30” finish heavy varmint, 5R,9 twist and a MBM 5 port beast brake. We’ll see how she’s performs once I get it back from Dave Tooley and get it in the manners stock lol
 
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Ledzep

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30" medium palma Bartlein here. Shipped yesterday. Will probably be a month or two before I get around to spinning it up.
 
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LakuNoc

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I'm Planing to build 300 PRC hunting rifle also some long range target shooting. 1000 yards and on, how heavy would you guys go for hunting rifle in 300 PRC?
 

b6graham

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I'm Planing to build 300 PRC hunting rifle also some long range target shooting. 1000 yards and on, how heavy would you guys go for hunting rifle in 300 PRC?
how much hiking/walking/stalking do you plan on having to do? Plenty of people, myself included, have hunted with 15+ pound rigs no problem, but i was only ever walking a few miles in
 
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jwknutson17

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I'm Planing to build 300 PRC hunting rifle also some long range target shooting. 1000 yards and on, how heavy would you guys go for hunting rifle in 300 PRC?
Just what b6graham said above.

Personally for me anything over 12 lbs loaded up is kinda overkill on a hunting gun specifically. I prefer good glass and that's why I set my weight to that. About 2.5 lbs for scope and rings. Could be little more if using a spuhr mount or alike. Maybe a pound about in mag, ammo, sling. Leaves you 9lbs for rifle, brake, maybe a TB ultra can, and maybe skip the bipod for hunting. I use shooting sticks. If you have a pound for a can and brake, you are at 8 for the gun. This is my top limit on high country hunting guns where I will be hiking a lot every day at elevation.

I am not weighing parts on every gun. I usually choose my parts that tailor to the job, then look at the weight. If it's going to get too heavy with my ideal parts, I then consider buying different parts as substitutes. With the CF proof sendero barrels and Manners CF stocks, it's pretty easy these days to get the weight down without sacrificing.

Lot of guys are looking at super light guns on magnums. And for me, they are much harder to shoot and recoil like a you know what. I would rather carry the 2 extra pounds personally.
 
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camotoe

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I'm Planing to build 300 PRC hunting rifle also some long range target shooting. 1000 yards and on, how heavy would you guys go for hunting rifle in 300 PRC?

I think you're better off building for target shooting. Then hual the rifle when hunting.

Or just buy a cheap 300wm hunting rifle. Tc compass was 200 after rebate with threaded barrel for a can or brake
 
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