[photographer]

I recently put together a new build (which is a pistol at the moment while I wait for my stamp) it has a noveske 10.5 upper - assembled from Noveske and it is sitting in front of a spikes H2 buffer and carbine spring (its 11" I measured).
Ive only had the opportunity to put down range maybe 150 rounds (110 Vmax) or so, with intermediate at best functioning from the upper.
I more times than not, usually after every 7+ rounds have the bolt lock forward without a round in the chamber. I also will have on occasion a round that doesnt seem to chamber completely into the barrel as well. I pull the trigger and nothing (seems that when I look @ the BCG that the round didnt seat all the way forward and you can tell the group is sitting a bit back though it does have a live round in there)

The upper with just one round placed in the mag and then fired, properly locks back the BCG after it is ejected. The rounds which are ejecting due so at about 4:30/5:00 O'clock to my side. The upper has been hand cycled 500+ times and is wet.

I am experiencing this same problem with both my barrett and c mags, and the buffer spring I received from spikes measures 11" and been used with both the H2 and now a standard weight buffer, but I can not seem to get this to fire correctly in succession...

Any suggestions, im all ears.
Thanks

[Clint]

Great description of the problem.

Just need to isolate variables.


Did you call Noveske?

Carbine length gas on 10.5",
leaves only 2.8 inches of bbl after the gas port.

That is short.

Do they recommend any type of muzzle booster?

The ejection angle indicates a slow BCG speed.

Was the bolt supplied with or headspaced to that barrel?


Does the ammo work in other weapons?
Are the necks thick?

Does the lower run with other uppers?
Mags not dragging on the BCG?

[photographer]

I have not made contact with Noveske yet, as I am hoping to get this ironed out by going through all the possible configurations first. Hoping that it might be operator/configuration error first and possible to be solved on my end.

Included with the upper is their KX3 supressor which is supposed to aid in back pressure, for boosting performance of the BCG.

The bolt and carrier were both included with the upper and I am hoping from their reputation that all possible checks were made to ensure proper fit and spacing. However the bolt cam pin has always seemed a little rough in its movement.

I should be receiving an order from SSA for rounds sometime today, and will try pushing a few down the barrel within the week. Then we should be able to give the variable of ammo a proper reference tested against the base of the Hornady rounds (and with fingers crossed can just blame all this on hornady)

As I got rid of my other setup to finance this 6.8 build I have nothing to test this upper on for compatability issues. And it does look like the mags are dragging on the carrier group but not anything more than normal, from what I can see.

Thanks for the reply. And here is a link to the upper from Noveske to give you any reference. Hopefully this gives you a bit more insight as to the specifics you were curious about.
http://noveskerifleworks.com/cgi-bin...since=&status=

[photographer]

SSA to the rescue!!

After trying to solve this short stroking problem for close to a month now and having done everything I could think of with little success including a lighter buffer and swapping lowers still no avail.

So low and behold I get my SSA 100gr nosler accubonds (TL) in yesterday and without a single hickup today everything fed through as smooth as silk.
I didn't have a single short stroke out of 2 mags and everything felt wonderful with what would seem a bit more punch too.

I guess the Hornady 110 Vmax either were a bad batch (I got 200rnds from cheaper than dirt) or they just couldn't perform in my setup for some odd reason.

PROBLEM SOLVED - it was the damn Hornady ammo

[Clint]

Glad you got it worked out.

The simplest explanation is usually the right one,
in this case, weak ammo causing short stroking.

Testing in another weapon may have shown the ammo to be weak.

Then again, the ammo may work fine in another weapon with a longer barrel and more operating margin,
yet cause issues in an extremely short barreled weapon.

[-k-]

We test fire with both Hornady and SSA for function. The Hornady we have functions just fine but there was a batch from a while back that used a different powder. I think you may have some of that batch.