Feeding Problems w/ 6.8 Upper -Help

[Sean King]

Any chance this *might* be an ammo issue? The reason I ask is I am new to 6.8 as well. What ammo is the original poster using and has he tried any other types?

I bought 11 CProducts mags over the 4th of July sale (and got a free one with my LW upper). I will tweak the feed lips as needed (unless Larry says not to).

I also recently bought 1200 rounds of SSA's new Extreme (small rifle primer) 6.8 SPC from Art. The tips of the bullets are EXTREMELY blunt and I'm a little concerned that they won't feed at all. The only reason I mention the tips is that I know with my Dad's Colt A2's, we had problems feeding anything that didn't have very pointed tips.....although I'm sure his uppers didn't have M4 feed ramps.

I'm waiting on SBR paperwork before I can actually assemble this upper on my lower, but I'm curious as to other's opinions.

Thanks for any advice.

Sean

[AR15barrels]

I also recently bought 1200 rounds of SSA's new Extreme (small rifle primer) 6.8 SPC from Art. The tips of the bullets are EXTREMELY blunt and I'm a little concerned that they won't feed at all.

Congratulations.
You have 1200 of the main reason mag lips need to be tweaked.
I believe that those blunt noses contribute to feeding problems that we see in the 6.8.
Personally, I have never experienced feeding problems with any 6.8 upper during test firing and I test fire every barrel I build, but then I have only test fired with remington ammo.

It's a sad state we are in where everyone buys the absolute cheapest ammo and then frets about their rifle not working well when they work great with better ammo.

You know how the QC triangle goes, you can have it cheap, you can have it fast or you can have good quality, pick any two...

[Sean King]

Congratulations.


It's a sad state we are in where everyone buys the absolute cheapest ammo and then frets about their rifle not working well when they work great with better ammo.

Cheapest???? At 58-59 cents a round, it's about the same as Remington (since you can get 20 for $11.79 or $.5895 cents per round from SG or any other number of vendors).

The reason I bought SSA was b/c just about everyone on Arf.com was saying how Remington's brass was too soft in the tacked 6.8 thread and many people were writing glowing reports of the SSA ammo and that they wouldn't be buying Remington.

Please check the attitude until you have the facts of my particular situation. I wasn't trying to be cheap.....perhaps I bought unwisely based on hype, but how was I to know any better? ***EDIT*** I will add that the friendly exchanges between you and Art in the 6.8 pinned thread don't make it readily apparent that you have a distaste for his "cheap" ammo.

Sean

[C4IGrant]

Soft tip or wad cutter type ammo will give any weapon troubles (whether it is a 1911 or an AR). AMMO sounds like it is the issue. Got any other ammo you can try?


C4

[AR15barrels]

Cheapest???? At 58-59 cents a round, it's about the same as Remington (since you can get 20 for $11.79 or $.5895 cents per round from SG or any other number of vendors).

The reason I bought SSA was b/c just about everyone on Arf.com was saying how Remington's brass was too soft in the tacked 6.8 thread and many people were writing glowing reports of the SSA ammo and that they wouldn't be buying Remington.

Please check the attitude until you have the facts of my particular situation. I wasn't trying to be cheap.....perhaps I bought unwisely based on hype, but how was I to know any better? ***EDIT*** I will add that the friendly exchanges between you and Art in the 6.8 pinned thread don't make it readily apparent that you have a distaste for his "cheap" ammo.

Sean

In general, I would try a few boxes of each ammo to see how it works BEFORE I bought a case or more.
Hopefully, you have no feeding trouble with the extreme bullet.
This has not been the case for many people though.
I have helped a lot of people tweak their mags.
Most of them are not even my customers.

I did nothing to give the extreme bullet it's reputation.
It earned it on it's own merits.
I have no problem with Art's ammo and we are on good terms.

I just really don't like that extreme bullet.
Art's been screwed by it a little too because it can't hold up to max pressures like traditional jacket & core bullets can.
When pushed to max presures, the tail of the bullet would obturate into the neck relief and then sometimes leave a copper ring which elevates pressures in subsequent rounds.
The solution was a longer throat that would support the tail of the bullet while it obturates.
By the fact that large quantities of this ammo made it to market quickly, the barrel makers were forced to re-work chambers so that the extreme ammo would be safe.
That's where my animosity towards that bullet stems from.
I'm sure it's a love/hate relationship for Art too, having to deal with complaints and make appropriate reductions in pressure/velocity to make it safe for everyone.

For the record, I have not had any problems with Remington ammo and that's what all my test firing is done with.

[Sean King]

In general, I would try a few boxes of each ammo to see how it works BEFORE I bought a case or more.
Hopefully, you have no feeding trouble with the extreme bullet.
This has not been the case for many people though.
I have helped a lot of people tweak their mags.
Most of them are not even my customers.

I did nothing to give the extreme bullet it's reputation.
It earned it on it's own merits.
I have no problem with Art's ammo and we are on good terms.

I just really don't like that extreme bullet.
Art's been screwed by it a little too because it can't hold up to max pressures like traditional jacket & core bullets can.
When pushed to max presures, the tail of the bullet would obturate into the neck relief and then sometimes leave a copper ring which elevates pressures in subsequent rounds.
The solution was a longer throat that would support the tail of the bullet while it obturates.
By the fact that large quantities of this ammo made it to market quickly, the barrel makers were forced to re-work chambers so that the extreme ammo would be safe.
That's where my animosity towards that bullet stems from.
I'm sure it's a love/hate relationship for Art too, having to deal with complaints and make appropriate reductions in pressure/velocity to make it safe for everyone.

For the record, I have not had any problems with Remington ammo and that's what all my test firing is done with.

Randall,
Thanks for the explantion. I apologize if my reply was a bit curt. The truth is: I'm a complete newb to 6.8 and I made the apparently ignorant assumption that the ammo issue was good to go regardless of who was making it. Not until AFTER I ordered my upper did I find out about the discrepancies with the SAAMI spec and I had no idea that the Extreme would have the blunt tip it does. Knowing what I know now, I was extremely stupid to buy a 1000 rounds (there was a billing error and I had Art pay the overcharge to me with more ammuniton) without first trying it. Coming from a .223 or 5.56 background, I didn't foresee any real issue as this first thousand was just to break in the rifle and most brass cased 5.56 is decent enough for this purpose. Apparently not so for 6.8.

In any case, thanks for the education. I guess the old saying still holds true. "Education is what you get when you read the fine print. Experience is what you get when you don't." This is going to be an expensive "experience" for me if the Extreme won't feed in my upper.

Thanks for the reply.

Take care,
Sean

[AR15barrels]

Randall,
In any case, thanks for the education. I guess the old saying still holds true. "Education is what you get when you read the fine print. Experience is what you get when you don't." This is going to be an expensive "experience" for me if the Extreme won't feed in my upper.

If the Extreme won't feed in your upper and mags as it comes, look at where the ammo is hitting and tweak the mag lips accordingly.
It's really that simple and it's not a big deal.

[SuicideHz]

I built an upper over the last two weeks for a friend who just moved up and got into AR15s. I used an LMT upper I had along with a brand new CMMG barrel with M4 extensions. We got through 30 rounds before having a FTF every other round. It appeared the left ramps didn't line up so I cleaned them up with a battery powerd teenie weenie dremel. I cleaned up both ramps. Then every round jammed while loading manually.

Eventually that same night I realized that the ramps were not the same as on my WOA SS barrel- my ramps widen as they approach the bore. The CMMG's do not and it was the narrow channels for the bolt lugs that were still very sharp from being so new that were grabbing every round and holding onto them.

Check your jackets for deep grooves on each side.

I ended up using 800 grit sandpaper wrapped around a 1/8" dowel to slowly polish the ramps in the upper and extension by hand.

It seemed to do the trick.

My pre-ban Labelle's didn't jam as bad as his new midwayusa stoner (c-products) mags but they still had a few. Problem was totally gone the next day using the c-products mags.

[Sean King]

If the Extreme won't feed in your upper and mags as it comes, look at where the ammo is hitting and tweak the mag lips accordingly.
It's really that simple and it's not a big deal.

Well, like I said, I plan to try that first (unless Larry says not to).....

I talked to Art today about the issue and he is willing to swap out the unopened Extreme for me if I can't get it to work in my upper. THAT, IMO, is excellent customer service. On the plus side, Art said he's just run 500 rounds of Extreme through a LW 10.5" upper and had no problems whatsoever.....hopefully, I'll fair as well.

I appreciate your time Randall. Thanks again for the advice and the education. You've helped me a lot.

Sean

[AR15barrels]

I talked to Art today about the issue and he is willing to swap out the unopened Extreme for me if I can't get it to work in my upper.

Art's a stand-up guy.

I fully expected that he would offer to credit you for un-opened ammo if it does not run in your upper.

Start out with the mags JUST AS THEY COME first to have a baseline.
Don't go making changes just because I said to.
Get a performance baseline before you determine if changes are even necessary.