Owner/Instructor at Semper Paratus Arms
Facebook: https://www.facebook.com/SemperParatusArms/
Semper Paratus Arms AR15 Armorer Course http://www.semperparatusarms.com/cou...-registration/
M4C Misc. Training and Course Announcements- http://www.m4carbine.net/forumdisplay.php?f=141
Master Armorer/R&D at SIONICS Weapon Systems- http://sionicsweaponsystems.com
Run some 5.56 ammo through it and see if the issue persists, if not there you go.
Gettin' down innagrass.
Let's Go Brandon!
The pistol lower I built is the only one I can legally use with the mk18 upper. I have a BCM upper and my dad has a DD upper, both 16" middies, that have been 100% reliable. The BCM is on a BCM lower with carbine spring and H1, and the DD is on a PSA lower with an unmarked buffer and their spring, presumably both carbine parts.
It's about midrange for .223, but I just checked Ramshot's website and it is indeed a starting load for 5.56. I can go as high as 27.3
http://www.ramshot.com/wp-content/up...2016_Web-1.pdf
Not partial to this load necessarily, but I am partial to handloading. I reload for around $0.12/round. Fortunately, it wouldn't add any significant cost to bump the charge weight up a grain or two.
I test fired it with a round of Federal XM193 and it locked back with the DD magazine, but I realize that's too small a sample to give any relevant data on the ammo or magazine (though I suspect you guys are correct that a 5.56 load would lock back). I can try some more 5.56, but I gotta buy it first. I honestly only have the 5.56 on hand for a course in September. Otherwise, I handload for barely more than half the cost of steel cased ammo.
I can't afford to shoot a ton of factory 5.56, so I want this gun to function reliably with my handloads. 24.5 is convenient because I load on an XL650 and I have a 62 gr BTHP load that is sub MOA at this charge weight. It's a PITA to adjust the powder measure, but I'm more than willing to bump up the charge weight on the 55 gr load if that makes this gun happy.
This may be the basis of your problem. If you are at the starting with Powder charge for .223 that it truly designed to be shot in a bolt gun. I certainly under the convenience side of what you’re saying but it sounds like your convenience is part of your problem. So in my opinion you have two choices. Either adjust your powder measure back and forth as needed or buy another tool head and powder measure you can switch. I’d be willing to bet you are causing your own problem. You could verify this but trying factory loaded ammo.
Just to clarify, this is a midrange .223 load, but a minimum 5.56 load. For .223 Ramshot lists 23.2 — 25.8, and for 5.56 they list 24.5 — 27.3 for 55 gr Hornady bullets seated at the crimp groove (2.200"). But you're right my current charge weight is likely the culprit in this gun.
http://www.ramshot.com/wp-content/up...2016_Web-1.pdf
I'm definitely going to try two things.
First, I'm going to buy a box of 5.56 and see if it locks a variety of my magazines back. Hypothesis: it will work perfectly
Second, I'm going to work up my handloads at .5 gr intervals up to 27.0 (max for 5.56 is 27.3). Hypothesis: the problem will probably go away at 25.0 and almost certainly go away at any charge higher than that.
Last edited by MWAG19919; 07-08-18 at 10:59.
I just got back from the range. Tested the gun with 5 different magazines (DD 32 round, Lancer L5AWM 30 round, Gen 3 PMAG 30 round, Gen 3 PMAG 20 round, and D&H 30 round). Loading one round into each magazine my dad and I shot 10 rounds of each ammo type.
Federal American Eagle 5.56 locked the bolt back 10/10 times
25.0 gr TAC locked the bolt back 4/10 times
25.5 gr TAC locked the bolt back 10/10 times
26.0 gr TAC locked the bolt back 10/10 times
26.5 gr TAC locked the bolt back 10/10 times
27.0 gr TAC locked the bolt back 10/10 times
Going forward I'll find a load between 26.0 and 27.0 that the 16" middies shoot accurately. That should give me plenty of wiggle room to find a decently accurate load that will still work when it's below freezing.
Great - sounds like your load was simply under gassed
Patriotism means to stand by the country. It does not mean to stand by the President... - Theodore Roosevelt, Lincoln and Free Speech, Metropolitan Magazine, Volume 47, Number 6, May 1918.
Every Communist must grasp the truth. Political power grows out of the barrel of a gun. Our principle is that the Party commands the gun, and the gun must never be allowed to command the Party Mao Zedong, 6 November, 1938 - speech to the Communist Patry of China's sixth Central Committee
Bookmarks