Larry D Posted March 5, 2011 Share Posted March 5, 2011 OK folks. Having solved the dilemma of the IMR powder, I've run into another issue. I ran 50 rounds of the new load to test. The AR15 blew about 90 percent of the primers out, while the Mini 14 didn't pop one single primer. I'm running 23.5 grains of VV N-130 behind an SS109 using once fired Lake City brass swaged on a Dillon swager. All expended brass shows no abnormal signs of a hot load (cratering, bulging, splits, cracks, etc.) I'm thinking the swager isn't set properly, but the fact that only 1 rifle had the issue is making me second guess myself. Any thoughts or suggestions from the gurus here? All input greatly appreciated. Link to comment Share on other sites More sharing options...
Kyle O Posted March 5, 2011 Share Posted March 5, 2011 adjust the swager, and load some test rounds. What velocity are you sending these? Link to comment Share on other sites More sharing options...
Larry D Posted March 5, 2011 Author Share Posted March 5, 2011 adjust the swager, and load some test rounds. What velocity are you sending these? 3100 FPS +/- Link to comment Share on other sites More sharing options...
wide45 Posted March 5, 2011 Share Posted March 5, 2011 check your firing pin. Link to comment Share on other sites More sharing options...
redmanfixit Posted March 5, 2011 Share Posted March 5, 2011 What chambering on the 2 guns? If you have 5.56 military brass in a .223 chamber you'll get pressure problems, depending on the load. Have you checked the length of the brass and/or trimmed any of it? OAL and seating depth of the bullet are important. If you have a short leade on the AR and a longer throat on the Ruger (likely) then you'll get pressure problems because the bullet takes too much to get moving!! Link to comment Share on other sites More sharing options...
Larry D Posted March 6, 2011 Author Share Posted March 6, 2011 (edited) What chambering on the 2 guns? If you have 5.56 military brass in a .223 chamber you'll get pressure problems, depending on the load. Have you checked the length of the brass and/or trimmed any of it? OAL and seating depth of the bullet are important. If you have a short leade on the AR and a longer throat on the Ruger (likely) then you'll get pressure problems because the bullet takes too much to get moving!! Can you give a layman's explaination of that. Specifically the short Leade VS longer throat issue? Brass is all trimmed to withing spec. Every stinking piece of it...(all by hand) I'm at 2.250 +/- for OAL Edited March 6, 2011 by Larry D Link to comment Share on other sites More sharing options...
Larry D Posted March 6, 2011 Author Share Posted March 6, 2011 check your firing pin. Firing pin is fine. I tested with factory ammo in the same mag. Link to comment Share on other sites More sharing options...
Larry D Posted March 6, 2011 Author Share Posted March 6, 2011 check your firing pin. Firing pin is fine. I tested with factory ammo in the same mag. Link to comment Share on other sites More sharing options...
Larry D Posted March 6, 2011 Author Share Posted March 6, 2011 check your firing pin. Firing pin is fine. I tested with factory ammo in the same mag. Link to comment Share on other sites More sharing options...
Larry D Posted March 6, 2011 Author Share Posted March 6, 2011 Ah geez... Sorry for the triple tap. Link to comment Share on other sites More sharing options...
redmanfixit Posted March 6, 2011 Share Posted March 6, 2011 5.56 military brass is slightly longer than .223. This is to accommodate the heavier, longer bullets often used in military ammo. Depending on the shape of the front part of the bullet, (called the ogive) it it may be engaging the rifling when the bolt goes home. Pressure goes up! Benchrest shooters, in order to gain greater accuracy, will measure the "free bore" on a rifle to seat the bullet just a few thousandths back from that part of the throat to prevent bullet from spending too much time in movement before it engages the rifling. So, beyond chambering there is the length of the leade. On off the shelf rifles, manufacturer's decide on specifications for the chamber and free bore that will make the rifle as safe as they can make it, by accommodating all but the most ridiculous loadings they think may reasonably be fed to a firearm. It's likely, that the free bore on the Ruger is longer than the free bore on the AR. It's possible that the bullet shape may be a factor. There are chamber gauges and freebore gauges that you could use to compare the two guns. You can also have a gunsmith do a chamber cast! Or, by using "dummy" rounds experiment on seating depth of the projectiles. PLEASE be careful! Of course, this involves putting brass with a bullet in it, into the rifle to see when the rifling begins to emboss the ogive and then backing off a bit. SAFETY SAFETY SAFETY!!! Barrel obstructions! Accidental discharges!!! Peril and death!!! There are lots of publications on how to make precision ammunition. Old reloading manuals often had information like this among the load data. Here in the future, lawyers have often counseled publishers NOT to include this information because it's pretty much inevitable that someone will fail to understand the instructions, blow a gun up and blame the author for their stupidity, then sue! (This is not the future I signed up for!!) The variables you have to deal with are understandable and with a little work you can produce VERY accurate and safe loads. That's the fun part!! The description you posted may have several causes. A too long firing pin or battering of internal structures on the bolt assembly could be the problem. It also could be a tight chamber and short leade. Remember that military brass is also thicker in the case walls, which can also cause problems when the load is near upper pressure limits, because of reduced case volume. When I load .223, I sort military head-stamps from civilian head-stamps for these reasons. I have been a long range shooter for many years, and there is a difference between the ammo I feed my gas guns Vs. that which I feed my bolt guns. Not too much of a problem if you're into it. There is a difference between 5.56 Nato and .223! The general rule is that you can feed a 5.56 chambered rifle, .223 but not the reverse. Everybody in the firearms industry is scared to death of lawsuits. Because of that, you may have to work a bit harder to ferret out the details. Find a CRABBY OLD benchrest shooter. Be polite to him, ask questions, and listen to what he says. It'll probably save you a bunch of time. OR go to auctions or garage sales, estate sales and get old reloading manuals! There's a TON of data in them that those OLD GUYS worked out and published before the world was infested by the plague of lawyers we have now!! BEWARE!!!! Benchrest shooting can lead to onset of Obsessive Compulsive Disorder!! (Hee Hee Hee) Do not ask me how I know this! Yes, I'm feeling MUCH better now!!! Link to comment Share on other sites More sharing options...
DinosaurMikeGolf Posted March 7, 2011 Share Posted March 7, 2011 What chambering on the 2 guns? If you have 5.56 military brass in a .223 chamber you'll get pressure problems, depending on the load. Have you checked the length of the brass and/or trimmed any of it? OAL and seating depth of the bullet are important. If you have a short leade on the AR and a longer throat on the Ruger (likely) then you'll get pressure problems because the bullet takes too much to get moving!! Can you give a layman's explaination of that. Specifically the short Leade VS longer throat issue? Brass is all trimmed to withing spec. Every stinking piece of it...(all by hand) I'm at 2.250 +/- for OAL Try this link. http://www.humanevents.com/article.php?id=41770 Link to comment Share on other sites More sharing options...
warpspeed Posted March 7, 2011 Share Posted March 7, 2011 Have you checked the headspace on the AR ? Link to comment Share on other sites More sharing options...
pjb45 Posted March 7, 2011 Share Posted March 7, 2011 I had a similar problem. Almost the exact same set up. Dillon super swage. What I noticed was that the primer hole on some brass needed to be reamed. Additionally,non-Lake City brass was more prone to have primer failure than LC. I had to back off my velocity to below 3100 fps for SMK 69 grain bullets. I did not have problems with LC brass. Link to comment Share on other sites More sharing options...
Powder Finger Posted March 7, 2011 Share Posted March 7, 2011 OK folks. Having solved the dilemma of the IMR powder, I've run into another issue. I ran 50 rounds of the new load to test. The AR15 blew about 90 percent of the primers out, while the Mini 14 didn't pop one single primer. I'm running 23.5 grains of VV N-130 behind an SS109 using once fired Lake City brass swaged on a Dillon swager. All expended brass shows no abnormal signs of a hot load (cratering, bulging, splits, cracks, etc.) I'm thinking the swager isn't set properly, but the fact that only 1 rifle had the issue is making me second guess myself. Any thoughts or suggestions from the gurus here? All input greatly appreciated. did the primers blank (pierce) or just fall out? if it's a big primer pocket issue (from swaging) you should have been able to feel that when you seated the primer. if the primer pockets were O.K. to start then you are TOO HOT for the rifle, components, assembly. IMO if it happens once you STOP and evaluate what's wrong. Also you are about .4 over on a fairly fast powder. Link to comment Share on other sites More sharing options...
Larry D Posted March 12, 2011 Author Share Posted March 12, 2011 The primers just popped out. No piercing, cratering etc. Link to comment Share on other sites More sharing options...
Henny Posted March 12, 2011 Share Posted March 12, 2011 I'm curious, what primers are you using? Link to comment Share on other sites More sharing options...
Powder Finger Posted March 16, 2011 Share Posted March 16, 2011 The primers just popped out. No piercing, cratering etc. If the primers seated fine and snug then you got too much pressure for the conditions. Link to comment Share on other sites More sharing options...
Larry D Posted March 19, 2011 Author Share Posted March 19, 2011 I'm curious, what primers are you using? CCI. Link to comment Share on other sites More sharing options...
Henny Posted March 19, 2011 Share Posted March 19, 2011 I'm curious, what primers are you using? CCI. 400s or 41s? Link to comment Share on other sites More sharing options...
Larry D Posted March 24, 2011 Author Share Posted March 24, 2011 I'm curious, what primers are you using? CCI. 400s or 41s? 400. I should have posted that. Link to comment Share on other sites More sharing options...
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