Gunsmithing cycling issues :(

[Ianski]

So just got this new Spikes tactical upper with a JP super match stainless barrel, spikes NiBoron bolt and a JP adjustable gas block.

-The issue:
1. wont cycle at all with any steel case(yeah, i know, a barrel like that shouldn't be insulted by using steel cased )

2. Partially cycle's with hornady V-max, ejects, resets trigger but does not feed and load next round.

I noticed that 2 of the set screws on the adjust able gas block were stripped, don't know if it has been removed or not, but i was thinking if it has maybe it wasn't rotated completely back over the gas port in the barrel.

any other ideas of what this beautiful upper's ailments may be?

 

[LRI]

Re: cycling issues

A speculative guess:

Steel cases are often coated with a laquer-ish coating to mitigate rust. The friction during extraction means your gas system has to be stout.

Factory ammo. Depending on the bullet weight it may/may not function well.

As you eluded, pick your gas system apart. Make sure the tube is indexed with the hole in the block. Make sure the barrel/block are aligned, make sure the gas key is tight on the carrier, and last make sure your gas rings are in good shape. Also, make sure the tube isn't worn where it fits to the key.

The way I was taught to check gas rings was by placing the assembled bolt carrier on a table. Bolt down with the carrier assembled. The rings should support the assy w/o collapsing. Hit the table with a fist. It should then collapse.

If all this is good. Go to quality ammo w/ heavy bullets. If it runs with that you either stick with it or open the hole in the barrel. If you do this, go in very small steps. Go too far and it'll rip cases up at the rim.

It should go back just enough to lock the carrier to the rear.

Good luck

C.

 

[sudnrush]

Re: cycling issues

Did you try simply adjusting the adjustable gas block? Maybe the gas is just turned down to much.