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Posted: 7/18/2012 2:55:54 PM EDT
Ok, three threads on the first page. I hope I am not getting too greedy  .
Different barrel/upper than the other posts I have. I have been testing 2 different types of ammo. Another 300BLK - First ones are GUNN reloads. 130 grain SOST bullet in resized used military 5.56 brass. - Second is CMMG 147 grain FMJ's. Actual new 300 Blackout brass. (CMMG stopped making it fyi) Upon inspection of the GUNN, some brass was imperfect, but I filtered that out and didnt use it for testing. Only used the stuff that looked ok. Every 2nd to 5th round would jam the tip of the bullet against where the shoulder of the case should sit (not sure the name of that part of the chamber). I initially thought it was catching on the feedramps, but I can see the brass marks from the tip of the bullet, and the tip is flattened out. The CMMG ammo ran fine and fed great. Granted the brass was new and much smoother, but for me this still does not compute. Logically I think it is the ammo, but if that is the case, I want to know why the other ammo wont feed. If there is a way to measure parts of it, if that would help, please let me know. I am going to post this in the 300BLK forum too, just to give it more exposure. Maybe others have had issues with the ammo. Thank you. |
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If the tip of the round is catching the shoulder of the chamber, then double check your mag catch button to confirm that the face of the threads are flush with the mag release button face. Right now, sounds like the mag is sitting low in the receiver (or the wrong mag in play), and causing too high of an attack angle of the rounds when feed into the chamber.
As for brass, way to easy to make it out of standard 223 brass, hence a quick trim of the stock 223 case*, forming (don't forget to lightly mica/lube the inside neck of the brass at this stage), then a quick unifying trim length of the lot with chamfering. Also a reminder, confirm that you sizer is touching the case holder under ram tension, even with new brass. Could just be that the brass in question what not correctly sized, and some of the problem as well. *Not sure if you caught the You tube video, but a lad bought a Harbor freight cheap tile saw to do the cut off part of the brass before forming. http://www.youtube.com/watch?v=smmRG0XZ7HE As for staying low budget on final trimming and chamfering, check with kwick trim if they can make you up a trimmer in 300blk, and then in just a matter of picking up a chamfer with drill adapter for deburing, then a trim through the tumbler to gleam the brass like a babies but. https://www.possumhollowproducts.com/KWICK_CASE_TRIMMERS.html |
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I'm not loading 300 but i just trim with the lee set up chucked in a drill.
I'll save up towards a dillon rt or a giraurd this video never ceases to make me jelous http://www.youtube.com/watch?v=c1FIs0FDmFQ |
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