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Discussion Starter · #1 · (Edited)
Was doing some load research today and had some trouble with my rifle short stroking. My rifle still seemed to shoot factory loads ok. Did not have this problem earlier this morning when the outside temp was still reasonable. My rifle has a 16" scout ARP barrel. my load was 28.5 grains of AA2200 putting 110gr Accubonds out of SSA once fired brass. OAL 2.295 and CCI 41 primers. I never thought to high of pressure would cause short stroking. Maybe someone here can enlighten me. Thanks for all the help.
 

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Why do you think your loads are hot?

What high pressure signs are you observing?

Have any good close up, in focus pictures of the fired cases...? Particularly the primer and rim?

28.5 g of AA2200 with a 110g is not a hot load.
 

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Discussion Starter · #4 ·
I'll try to get a pic when I get home. At 28.8grs I had blow by on the primer and deep swipes. I forgot to mention earlier that I also crimped each load.


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I'll try to get a pic when I get home. At 28.8grs I had blow by on the primer and deep swipes. I forgot to mention earlier that I also crimped each load.

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Perhaps you are over crimping. You should not see those kinds of pressure signs from that relatively mild load. That's nowhere close to "hot". Try some of the same loads without a crimp. You don't need to crimp anyway so eliminate that step. Roll crimp? If so, definately stop doing that. You'll never build accurate ammo with a roll crimp using your seating die.
 

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Discussion Starter · #7 ·
This is my 28.8 case. I loaded up three of these but after this one I didn't push my luck.


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Discussion Starter · #8 ·
Perhaps you are over crimping. You should not see those kinds of pressure signs from that relatively mild load. That's nowhere close to "hot". Try some of the same loads without a crimp. You don't need to crimp anyway so eliminate that step. Roll crimp? If so, definately stop doing that. You'll never build accurate ammo with a roll crimp using your seating die.
I'll take that advice. I thought that I needed to crimp. I've done a lot of loading for bolt guns and never used a crimp.

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Make sure the bolt tail is clean. My PSA 6.8 always starts short stroking whenever the carbon starts to build up on the bolt tail. Usually around 300-350 rounds fired. A light crimp is ok. Lee crimp dies are excellent for a light crimp and cheap. Regarding the swipes, a Spike's ST-T2 heavy buffer should reduced the swipe marks.
 

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Discussion Starter · #10 ·
Make sure the bolt tail is clean. My PSA 6.8 always starts short stroking whenever the carbon starts to build up on the bolt tail. Usually around 300-350 rounds fired. A light crimp is ok. Lee crimp dies are excellent for a light crimp and cheap. Regarding the swipes, a Spike's ST-T2 heavy buffer should reduced the swipe marks.
What are you referring to as the bolt tail? Are you talking about the narrow part of the bolt that goes into the carrier? The weird thing is the rifle worked fine with factory SSA 110 Pro Hunters.
 

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What are you referring to as the bolt tail? Are you talking about the narrow part of the bolt that goes into the carrier? The weird thing is the rifle worked fine with factory SSA 110 Pro Hunters.
Yes. Just behind the gas rings. Mine is like clockwork, every 300-350 rounds and it starts. And the carbon is not really that heavy. But after I clean the bolt tail, shoots fine. Odd that I never had to clean the tail on any of my 5.56 or .308 ARs.

BTW, the CAT M-4 is good tool to clean the tail since you have to scrape off the carbon. You can normally find them on sale for around $25-30. Here's a link:

 

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Yes. Just behind the gas rings. Mine is like clockwork, every 300-350 rounds and it starts. And the carbon is not really that heavy. But after I clean the bolt tail, shoots fine. Odd that I never had to clean the tail on any of my 5.56 or .308 ARs.

BTW, the CAT M-4 is good tool to clean the tail since you have to scrape off the carbon. You can normally find them on sale for around $25-30. Here's a link:

http://shop.ironworkstactical.com/ProductDetails.asp?ProductCode=CAT-556

Brett C.
IronworksTactical.com - owner
 

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What are you referring to as the bolt tail? Are you talking about the narrow part of the bolt that goes into the carrier? The weird thing is the rifle worked fine with factory SSA 110 Pro Hunters.
Are you absolutely certain of the accuracy of your scale? I shoot a load with 28.8gr of AA2200 behind a 110gr SPH and never see swipes like that. Fact is, even though that's approaching max I see no swipes at all. But, again, I also don't crimp.
 

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Discussion Starter · #15 ·
Are you absolutely certain of the accuracy of your scale? I shoot a load with 28.8gr of AA2200 behind a 110gr SPH and never see swipes like that. Fact is, even though that's approaching max I see no swipes at all. But, again, I also don't crimp.
Yes, I use two scales. One is a Hornady Lock and Load Auto Charger and the other is a Dillon Precision Digital. I'm really leaning towards the crimp as probably being most of the problem. The factory rounds aren't crimped.
 

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It depends, you got any pictures of this gal?

Oh, your talking about your rifle, lol.....

Sorry, I read the title of the thread and couldn't resist.
 

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I need to point out that my 6.8 short strokes with all ammo when the carbon builds up. So a heavy crimp may be the problem if your not short stroking on manufactured ammo. But, never hurts to rule out carbon buildup as culprit.
 
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