Page Index Toggle Pages: 1 [2]  Send TopicPrint
Very Hot Topic (More than 25 Replies) primer pocket shims (Read 1363 times)
notlwonk
Full Member
***
Offline



Posts: 124
Joined: Dec 18th, 2006
Re: primer pocket shims
Reply #15 - Mar 17th, 2019 at 8:25am
Print Post  
Making a punch and die would simplify the making of brass/aluminum/?? washers...well......once the die is made it would be simple.
  
Back to top
 
IP Logged
 
JLouis
Frequent Elocutionist
*****
Offline



Posts: 6551
Joined: Apr 8th, 2009
Re: primer pocket shims
Reply #16 - Mar 17th, 2019 at 1:59pm
Print Post  
Cheatin_Charlie and Gunlaker thank you for also sharing your information on the breech block damage created from Large Pistol primer use. Hopefully it will keep others from damaging their breech blocks by listening to those who would encourage their use. Luckily the last one destroyed in our group had a bushing that took the abuse and was inexpensively replaced.
  
Back to top
 
IP Logged
 
OLD TUCK
Full Member
***
Offline



Posts: 233
Location: Middleborough MA
Joined: Oct 5th, 2017
Re: primer pocket shims
Reply #17 - Mar 17th, 2019 at 5:11pm
Print Post  
Guy's I have over the years heard of this concern a few times. Early on a I spoke to friend about it and he agreed it might happen. His response was I now seat my Pistol Primers in a Large Primer pocket FLUSH so there is no running start for the Primer to beat up the breech block face. I left it off at that and have never concerned myself. Regards, FITZ. OLD TUCK Smiley
  
Back to top
 
IP Logged
 
gunlaker
Frequent Elocutionist
*****
Offline



Posts: 1709
Location: lower mainland
Joined: Dec 13th, 2010
Re: primer pocket shims
Reply #18 - Mar 17th, 2019 at 5:25pm
Print Post  
I have been using the paper under the primer trick in my CPA rifles and a couple of my highwall repros. 

If I were a machinist I would have a try at making the swaging tool.   I have this feeling that most of you guys are at the very least, home machinists, if not professionals.

I was amazed several years ago when I shot in Tacoma with Bob, Jack, and the rest of the Washington state people.  It seems that everyone but me had machining and gunsmithing skills.

Chris.
  
Back to top
 
IP Logged
 
boats
Frequent Elocutionist
*****
Offline



Posts: 6642
Location: Virginia
Joined: Apr 23rd, 2004
Re: primer pocket shims
Reply #19 - Mar 17th, 2019 at 6:32pm
Print Post  
My main CPA has been in use since 1994, brief use lgRifle Mag primers then to Large Pistol probably 10,000 CF shots no issues with the breech block, well over 10,000 RF.  Switching barrels and block one reason I like Lg Pistol. Run the same Hammer spring tension CF RF and the lighter RF Hammer setting makes the gun easier to cock.

Boats
  
Back to top
 
IP Logged
 
uscra112
Frequent Elocutionist
*****
Offline



Posts: 2594
Location: Switzerland of Ohio
Joined: May 7th, 2007
Re: primer pocket shims
Reply #20 - Mar 17th, 2019 at 7:50pm
Print Post  
I don't have a dog in this fight , but I'm mighty skeptical of pistol primers "peening" a breechblock.   

Can someone post pictures?
  
Back to top
 
IP Logged
 
cheatin_charlie
Full Member
***
Offline



Posts: 208
Location: ohio
Joined: Jan 10th, 2009
Re: primer pocket shims
Reply #21 - Mar 17th, 2019 at 10:11pm
Print Post  
For what it is worth I have never heard of peening of the breech block using smokless powders.  I believe it is when using full power loads of black powder that causes the problem.  Black is a low grade explosive and creates instant pressure compared to smokless.  The primer gets blown back with more velocity than with smokless.  I am not an engineer but that is my theory for what it is worth.  I fixed my rifle and shot rifle primers and did not have anymore problems.  And I only had .002 head space when I built the rifle and it did not increase with use.  Now with my 32-40 using paper under the pistol primer the primer is flush with the rear of the case.
I will continue to use pistol primers without the paper when using smokeless powder with no fear of peening the breachblock.
  
Back to top
 
IP Logged
 
JLouis
Frequent Elocutionist
*****
Offline



Posts: 6551
Joined: Apr 8th, 2009
Re: primer pocket shims
Reply #22 - Mar 17th, 2019 at 10:40pm
Print Post  
The only ones damaged that I know of was while they were using smokeless powders and not while using Black?
  
Back to top
 
IP Logged
 
RemFan
Newbie
*
Offline



Posts: 7
Joined: Jan 27th, 2019
Re: primer pocket shims
Reply #23 - Apr 11th, 2019 at 12:36am
Print Post  
one might want to consider, and I suspect someone on here already has,  researched the primers to start with.  Some primers are hotter than others.  It may be worth trying the brand that is the "least" hot.  If printed material is not available, and I know it is on shotshell primers, a good chronograph would be a big help .
  
Back to top
 
IP Logged
 
hepburnman
Full Member
***
Offline



Posts: 116
Location: NJ
Joined: Mar 22nd, 2015
Re: primer pocket shims
Reply #24 - Apr 11th, 2019 at 9:03am
Print Post  
I've never used pistol primers to try and get as low a primer force as I could. I've always had the opposite theory to try and get maximum primer force for cleaner burned blackpowder and also maximum velocity. In my 40-65 I use 70gr of 1. 5Fg and Fed 215 Mag primers for a 428 gr bullet. At a match last month during the practice session I shot this same load but some were with 215 primers and others with CCI BR2 primers. The BR2 primers were about 4 MOA lower on the Ram compared to the 215 Mag primers. I believe that the 215 primer are giving me a more complete burn of this charge weight.
I also use the 215 primers in my light load for chickens or 63 gr of 1.5 Fg under a 410 gr bullet.
I also cam my rounds into the rifling when I raise the breachblock and I do not use neck tension. If you use neck tension and load with some bullet jump than maybe my recipe would not work for you and perhaps a light primer force is the correct one to use.
  
Back to top
 
IP Logged
 
Bent_Ramrod
Frequent Elocutionist
*****
Offline



Posts: 1008
Location: Southern Arizona
Joined: Feb 8th, 2006
Re: primer pocket shims
Reply #25 - Apr 11th, 2019 at 9:47am
Print Post  
There was much discussion of the “peened breechblock syndrome” on the Shiloh Sharps site; probably ten years or more back.  IIRC, most of it was in connection with the general inferiority of Italian copies of black powder rifles vs. the American versions.

When it became obvious that the better Italian copies had none of the poorly-hardened parts that allegedly peened themselves into uselessness in a few shots, the defenders of American infant industries switched gears from metallurgical expertise to international currency expertise, claiming that an American replica could be gotten for the price of a couple Happy Meals more than an Italian one, given the fluctuation of the Euro vs. the Dollar on the Swiss Bourse, dont’cha know.  With about the same nodding acquaintance with the truth as the other accusation.

Certainly a poorly-hardened breechblock will show peening, no matter who makes it, but I have seen none of this phenomenon in either my US or Italian blackpowder rifles, and I use Federal GMM Large Pistol primers, with primer wads punched by the primer on seating.

The idea there is to generate the mildest impulse possible, so the powder column doesn’t break up and the bullet doesn’t move appreciably before the powder charge itself starts to burn.  It seems to work, for me at least; I get better targets with the wads than without them.  It might well be voodoo; I read an article way back when (in Rifle or Handloader, can’t remember which) where the author queried the component manufacturers and found that there is exactly the same weight of priming compound in Rifle and Pistol primers of a given size and type.  The only difference, they said, was the relative hardness of the cups, and, of course the depth difference in the Large versions.

I use strips of paper cut from Official ASSRA targets for the primer wads.  The paper is very uniform, of a good thickness, and, since all the holes are in the exact center,  Roll Eyes there’s plenty of paper left to repurpose.
  
Back to top
 
IP Logged
 
.22-5-40
Oldtimer
*****
Offline



Posts: 704
Joined: Feb 13th, 2010
Re: primer pocket shims
Reply #26 - Apr 11th, 2019 at 3:30pm
Print Post  
After reading all the replys, I probably have worried over a non issue.  Anyway..here is what I tried.  Using a Whitetail carbide large primer pocket uniformer, I uniformed 5 new Win. .32-40 cases.   The uniformer leaves pocket .130" deep.   Turned up .2105" dia. brass rod with .062" thru hole & parted off at .012" thickness.  These were pressed in with high strength lLockTite & allowed to fully cure.  I then used a carbide large pistol pocket uniformer to bring pocket to proper depth.  The problem is there is only about .006" to .007" thickness left on shim after this and 4 out of the 5 came out during this operation.  The solution would be to deepen original pocket to allow thicker shim..but this is something I would not care to do.
   How would a swaging tool work..it seems metal would need to come from somewhere and thinning brass at bottom of pocket seems to be the only way.  Again, probably nothing to worry about with a proper heat-treated breech face.  I did give RCM a call..they are still taking orders..I was going to ask for some .32-40 Everlasting cases for breech-seating with L.P. pockets..but was told they had problems with .32-40 cases cracking and will not make this size.
  
Back to top
 
IP Logged
 
Page Index Toggle Pages: 1 [2] 
Send TopicPrint