Just picked up a Carbon-15 .22LR upper from another member. Looks real nice, feels nice, shoots like crap

The rifle does not fully go into battery after firing the first round. Tried all kinds of ammo to no avail. Bolt is spotless and well lubed with Miltech.

It seems as though the bolt is either too slow or binding on return prior to locking closed. (The bolt does freely slide back and forth when the upper is seperated) When it does this, the extractor does not grab the rim, and the cartridge appears to seat too far into the barrel, thus causing light strikes or no strikes at all. It will also not extract the round because the extractor is not under the rim. You can see that the bolt is not fully closed.

Is it a buffer spring problem? (I have an A2 stock and am using the White tube, then the Gray tube in front).

Is it a hammer sping problem? (Is the factory Bushmaster hammer spring to heavy too allow for the short lock up required) If it is a hammer spring issue, where can I get a lighter faster spring? I am NOT looking to spend $100 for a new adjustable trigger, only need the different spring.

Is it something else?

Seller said it worked just fine for him on his Bushmaster lower with light springs.

Anyone experience this problem in the Carbon-15 upper?

If anyone experiences this problem, here is the solution......Do NOT use any type of match ammo. It does not have enough power to throw the bolt back with enough speed to get the proper bolt closure. I called Bushmaster and was told to use HIGH velocity ammo such as Blazer, CCI Mini Mags, etc. It worked out great. Also note, do not use any type of Hyper velocity ammo as it can cause damage. USE HIGH VELOCITY AMMO

Bump with solution..............