12" monster barrel and bolt

[BluntForceTrauma]

[Zjohnson611]

10/4 but yes I haven't had any failures with factory brass only with wolf steel case. And I have 2 other bolts that will not seat in the in the extension unless forced in and then it feels like you are going to break the charging handle trying to pull it back out with nothing in the chamber. And the other bolts are g2g in my bca barrel

[A5BLASTER]

10/4 but yes I haven't had any failures with factory brass only with wolf steel case. And I have 2 other bolts that will not seat in the in the extension unless forced in and then it feels like you are going to break the charging handle trying to pull it back out with nothing in the chamber. And the other bolts are g2g in my bca barrel

Take the o-ring off from under the extractor and see what it does with steel cased ammo.

[Wethepeople]

What A5 said. I had the same problem this morning w/ my monster bolt/barrel when I test cycled dummy rounds with steel case. Removed the extractor oring and it cycles perfectly.

[rabiddawg]

10/4 but yes I haven't had any failures with factory brass only with wolf steel case. And I have 2 other bolts that will not seat in the in the extension unless forced in and then it feels like you are going to break the charging handle trying to pull it back out with nothing in the chamber. And the other bolts are g2g in my bca barrel

[Wethepeople]

Missed that rabiddawg, thanks.

[A5BLASTER]

Maybe not but we will never know if he doesn't check it.

My thinking is it's something to do with the o-ring creating to much pressure when trying too work with the harder steel caseing.

If the chamber works with brass cases then it should work with steel cases as well.

The only thing I can see causing the issue is the o-ring.

It's a quick test and will either proff irs the problem are that the problem does indeed lay in the barrel.

[BluntForceTrauma]

I need help I put together a 12" monster barreled grendel and it was getting hung up at first so I lubed and shot it to loosen it up and still having feeding issues with only steel case ammo.

10/4 but yes I haven't had any failures with factory brass only with wolf steel case.

It's short stroking will no pick up the next round.

Thinking about this. Often things will be tight when new and loosen up as the parts work into each other.

Works with other factory ammo but not Wolf.

Wolf is notoriously underpowered.

What if your gas system has some kind of blockage, as if the gas block was not well-aligned with the gas port?

This could explain early troubles with all ammunition, but then as parts worked in and the whole system loosened up, only the underpowered Wolf remained affected by some gas blockage, leading to short stroking?

Bolt works in another gun with a different gas system?

Double-check the gas system?

Then, again, doesn't explain multiple bolts fitting tight in an empty chamber....

If bolt-to-extension fit is too tight, I suppose that drag could slow down the carrier velocity enough that it shows up on underpowered Wolf, manifesting in short stroking.

Couple theories here. Will check when I receive it.

[Zjohnson611]

I sent bolt and barrel back to you I believe they should be there today. I looked at it before I sent it back it looks like the feed ramps are off

[Huckleberry75]

My 12" group buy bbl has a just a hair of overhang with the feed ramps. Bbl feed ramps stick out just a smidge past the m4 cuts in my LMT upper. It does not feed the Federal 90gn TNT factory load worth a rip. Meplates get hung up on the lip and it just jams the bullet into the case. Going to put the barrel into a Precision Firearms upper and see if it still snags /hangs over. The barrel is quite accurate and I love the weight / length, just need to sort these feed ramps out and it will be GTG.

[A5BLASTER]

My 12" group buy bbl has a just a hair of overhang with the feed ramps. Bbl feed ramps stick out just a smidge past the m4 cuts in my LMT upper. It does not feed the Federal 90gn TNT factory load worth a rip. Meplates get hung up on the lip and it just jams the bullet into the case. Going to put the barrel into a Precision Firearms upper and see if it still snags /hangs over. The barrel is quite accurate and I love the weight / length, just need to sort these feed ramps out and it will be GTG.

You could probably blend the feed ramps into each other with a dremel and hone and then smooth them up with a soft tip and some polishing compound.

[FRB6.5]

Or use shims to bring the barrel forward from the upper.

[Huckleberry75]

You could probably blend the feed ramps into each other with a dremel and hone and then smooth them up with a soft tip and some polishing compound.

If it does the same thing with the second upper, that will most likely be my solution. Take it slow and polish it up with Flitz and buffing tip.

[Huckleberry75]

Here is what the feed ramps currently look like. Cutting lots of copper off the nose and gouging some of the side of the ogive. I may need to soften the corners on the center lug face that is catching the bullets as they go by to chamber.

[BluntForceTrauma]

Did you mention anything about magazines? Maybe one brand feeds rounds slightly higher than another?