6.5 PRC Over pressure with H1000 and 156 Bergers

Aloha All

Just wanted to post this here to see if anyone has anything similar happen to them. With this powder/bullet combo. Thanks in advance!

Have a buddy who hads a 6.5 PRC giving him issues on a hunt right now.

Here's his load specs:
New adg brass,
F215M
60gn h1000,
Berger 156 eol,
coal 3.0735,
cbto 2.360 = 15 thou off the lands

He told me he spoke to berger to get chg weights for H1000 & this cartridge/bullet combo. He was given 54.5 start 60.4 Max. He did note that they wouldn't give him brass brand they were using.

He did load work up from 56-60.5, 60.5 had very slight bolt lift resistance, Not heavy etc! Settled on 60 gr load less than .5 groups.

Below is what he had from LR for velocity. Until yesterday he had shot roughly 30 rounds with no pressure signs etc. Temps here are mid to high 80's

So he checks zero yesterday before today's hunt and first 3 shots all blown primers heavy bolt lift. He's scratching his head and bummed because he only took 20 rounds of 143's with him which he's already shot 10 lol.

Only thing that comes to mind is if the ADG Brass has a different volume than what berger was using (I'm thinking hornady?) Therefore the ADG Max is less than what berger is using. BUT...he worked up loads and none showed high pressure signs.

Idk what ppl seeing for velocity with this bullet but I told him that what he's getting is up there. But idk much about the PRC. I have a 6.5x284 n only doing 2950 with 130's.

He's got meat in the cooler so I told him I'd try and ask if anyone has ideas on the forums.

Sorry, his rifle is built on a tikka action. Started out as 300 Win mag. Had gunsmith rebarrel it with a proof sendero 7.5 twist 26" Put it in a woox exacts stock l believe.
Berger gave me 57.8 max with RL26. I found pressure at 57.6. & shoot at 57.0. You buddy needs to check the data Hornady gives on a 153 A-tip which finds pressure in my gun at almost the same place as a 156 EOL. I feel assured your buddy is shooting above safe pressure. My 2 6.5 PRC are both built by GAP. I shoot LRPs, Lapua brass, 57.0 RL26, Lapua brass, & 156 EOLs in one & 153.5s in the other. For whatever reason everything the Berger Tech has given me as max didn't leave any room to spare at all. Please consider looking at 153 A-tip data. Yes, bearing surface is different, etc, etc. but you will not be able to rationalize the discrepancy. Good luck on finding safe load and stay safe.
i'll go look in my 65 PRC data book & post where I found pressure with H1000 with the 156s.
 
Very good info here. My max was 59.5 using Hornady brass and found a very good node at 58.6 with the 156's. But, everyone in a while I was get heavy bolt lift and ejector swipe, primers always look fine. I know I am probably running a little hot but I thought it was strange to get heavy lift 1 out of 20 rounds. Maybe exactly what you are saying here. I'll also trim the next go around. Hopefully this will solve my issue or I just need to go down to the lower node!
For clarification - Running a 22" Proof at 2915MV ES 8-12 with 58.6 H1000 and 156 Berger's got 275 rounds down the barrel.
By the way they are bad medicine on my GA whitetails! Furthest shot out to 400 yds.
Just an update for you guys, the load I was using 58.6g of H1000 has now been determined as Hot. The primer pockets on my Hornady brass let go after only 3 firings. I have some Lapua brass on the way so I will start down near 48 grains of H1000 and work up to maybe 55. Anyone running above 58g please be careful and really pay attention to your bolt lift and brass warning signs. My brass was trimmed properly and the 156's were seated 5 thou off the lands so the only thing I can figure is just too much powder.
I'll report my findings on the Lapua brass once I finish load development.
 
Just an update for you guys, the load I was using 58.6g of H1000 has now been determined as Hot. The primer pockets on my Hornady brass let go after only 3 firings. I have some Lapua brass on the way so I will start down near 48 grains of H1000 and work up to maybe 55. Anyone running above 58g please be careful and really pay attention to your bolt lift and brass warning signs. My brass was trimmed properly and the 156's were seated 5 thou off the lands so the only thing I can figure is just too much powder.
I'll report my findings on the Lapua brass once I finish load development.
Be careful with minimum loads. IMR lists 49.5gr of H1000 as a minimum for the 153gr bullets, so a min for a 156 is likely not far below that. I would call Berger before loading only 44gr and trying it.
 
Just an update for you guys, the load I was using 58.6g of H1000 has now been determined as Hot. The primer pockets on my Hornady brass let go after only 3 firings. I have some Lapua brass on the way so I will start down near 48 grains of H1000 and work up to maybe 55. Anyone running above 58g please be careful and really pay attention to your bolt lift and brass warning signs. My brass was trimmed properly and the 156's were seated 5 thou off the lands so the only thing I can figure is just too much powder.
I'll report my findings on the Lapua brass once I finish load development.
Thanks for the update, mine fall into that category, and I have the same brass. I am thinking of dropping to 140 bergers or 143 ELDx
 
Thanks for the update, mine fall into that category, and I have the same brass. I am thinking of dropping to 140 bergers or 143 ELDx
HELP! Sight manager, this is my only link to Long Range Hunting. You stopped sending your daily 9:49am emails on 6/21/22. I don't know why. I'm at a loss on how to sign back up. Please send instructions on how to sign up for emails. l don't have an avatar. Thanks.
-Old Infantry Guy.
 
For what it's worth, I'm shooting a Seekins Element with a 21" barrel. With the Berger 156's and H1000 in ADG brass, my sweet spot is 55.7 gr. It's right at 2805 and tack-driving accurate. This was 5-shots at 100 yards with it.
4E7C3D3F-73AA-49E7-945D-8CC39E3D17D4.jpeg
 
For what it's worth, I'm shooting a Seekins Element with a 21" barrel. With the Berger 156's and H1000 in ADG brass, my sweet spot is 55.7 gr. It's right at 2805 and tack-driving accurate. This was 5-shots at 100 yards with it.View attachment 376947
Great group, thanks for the info....I am over 59grs but my velocity was 2930. I am going to get out again soon and retest.
 
HELP! Sight manager, this is my only link to Long Range Hunting. You stopped sending your daily 9:49am emails on 6/21/22. I don't know why. I'm at a loss on how to sign back up. Please send instructions on how to sign up for emails. l don't have an avatar. Thanks.
-Old Infantry Guy.
On your computer or laptop go to the site and do not log in if you automatically log in then log out and wait one minute and see if a photo with big horn sheep shows up. That will be the pop up that encourages you to signup for the newsletter

Len
 
On your computer or laptop go to the site and do not log in if you automatically log in then log out and wait one minute and see if a photo with big horn sheep shows up. That will be the pop up that encourages you to signup for the newsletter

Len
Apparently, I'm signed up to receive your newsletter. We'll see if it shows up tomorrow at 9:49am in my emails. Could not find the big horn sheep photo. We'll see.
 
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Len Baccus:
I have now officially given up on receiving daily emails. I've tried the things you suggested, plus a bunch of other things. Nothing has worked. Still no emails. Now I have to figure out how to stop the small pittance I send you monthly. I miss LRH. ......C Edwards
[email protected]
 
The thread is getting long. I skipped over a bit but will catch up on it later. I am running 156 eol with H1000, ADG, f215m, etc. 57 grains at 2873 with no issues with 72 rounds fired.
 
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The thread is getting long. I skipped over a bit but will catch up on it later. I am running 156 eol with H1000, ADG, f215m, etc. 57 grains at 2873 with issues with 72 rounds fired.
You should gain some speed after a few more rounds. My Proof sped up at about 200 rounds. I think it was about 50fps over all.
 
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