Reliable Cycling Case Prep

[asforme]

Hello all, this is my first post and am looking for some advice, tips or tricks.  I currently reload for my AR15 & AR10 and use the same procedure. I have never had a single problem with my AR15, however a reliable hand-load for my AR10 has alluded me.   I am now in the preliminary stages of reloading for a 6.5 CM on an AR10 platform.  I would like to implement a case prep procedure to produce reliable cycling rounds.   Has anyone experienced cycling issues with the 6.5 CM/AR10 and remedied the problem?  This old dog want to learn new tricks.  Thanks. . . . . . asforme

[Snaploader]

Hello all, this is my first post and am looking for some advice, tips or tricks.  I currently reload for my AR15 & AR10 and use the same procedure. I have never had a single problem with my AR15, however a reliable hand-load for my AR10 has alluded me.   I am now in the preliminary stages of reloading for a 6.5 CM on an AR10 platform.  I would like to implement a case prep procedure to produce reliable cycling rounds.   Has anyone experienced cycling issues with the 6.5 CM/AR10 and remedied the problem?  This old dog want to learn new tricks.  Thanks. . . . . . asforme

What kind of cycling issues?   As a rule, cycling issues are a problem with the rifle's set up with regard to gas block/tube; bolt carrier group; buffer weight and buffer spring.  Please be more specific and we shall help!

Mike

[asforme]

Well, it started out with cases sticking in the chamber, I solved that by resizing with a short base resizer.  Then cases would not fully extract from the chamber. I fixed that by enlarging the gas hole in the barrel.  Then after extraction, the new case would not fully chamber, so I fixed that with a different buffer spring.  Keep in mind these issues did not occur on every round.  For sanity purposes I went out and purchased 2 boxes of plain jane Winchester 147Gr FMJ cartridges and shot them all and not one  had a problem.  Currently the gun is shooting good enough, however still has a quirky round every 25 or so.  At this point I have decided to try commercial brass instead of military brass.   I am going to try and duplicate the Winchester round.  So back to the Creedmoor. . . . . .

[eas1949]

Try a small base body die.

Eric

[KRC]

Try a small base body die.

Eric

^^^ What he said . . .

And once you've got the case body resized, you can use a set of Competition shellholders or shellholder shims to resize the shoulders up as needed, as the SB dies usually setback the shoulders farther than needed. Or set the die a few thousands off the full stroke ram. (I find the +.00X" shellholders more repeatable than gapping the die.)

[Kansaswoodguy]

Are you running a wet BCG?

[Cold Trigger Finger]

Asforme;
 Welcome to the Creedmoor forum !
 What brand is your AR10 6.5 Creedmoor ?
 I'm interested in getting one of the PSA 65s but would prefer one with an 18" barrel. As I will be using it for hunting.
 

[bfoosh006]

Install an Adj. GB.

To me your issues sound like classic excess gas issues.

With excess gas ... come extraction issues while the case is still under high chamber pressures.

Faster then acceptable cyclic speeds, and ejection issues.

Cases not fully chambering could be bolt lugs not fully broke in... any marks on the cases ?

Honestly, given the complete lack of any Mil-Spec guidelines for the various manufacturers to follow... I consider the Large Frame AR a beast unlike the AR15.