Ruger American Repaired for Extraction issue

[grendelnubi]

From the time I took my RAP it out of the box, it would not pickup nor extract my used Hornady brass out of the chamber, even after firing the round.

I fully intended to use Starline brass with it anyway, so I tested Starline and it extracted perfectly. I did contact Ruger and let them know of my out of box issue. They told me I would have to send it back for them to investigate. I let them know it could be related to my well used Hornady brass because my brand new Starline worked just perfectly. I indicated this was just shared for an FYI....... and I would keep my eyes on it.

About a 1000 rounds later I started having extraction issues with my Starline brass. Contacted them again and sent it back with a fired case. As a side note, I was also getting primer cratering when running higher pressure loads.

They ended up replacing my bolt and I noticed the barrel was rotated slightly. After doing some measurements it appears the issue was excessive head space. Based on my fired brass, the HS was reduced from, 1.212 to 1.207 (.005). Now picks up both used Hornady and Starline brass. Primer cratering also went away, possibly due to the different bolt or do you think primer createring could also be related to excessive headspace?

[Klem]

Nubi,

Doesn't sound like headspace - more like a bolt issue which has been fixed at the factory.

From the SAAMI blueprint Grendel brass is permitted up to a 0.0171 stretch. This is from a rifle chambered at the max 1.2301", firing a round at the min 1.213". In your case you are talking about a .005" stretch which is tiny, almost as much as my brass stretches every time it fires. Sounds like both headspaces: before and after the change in bolts are fine.

Primer cratering is typically from hot loads, with the primer extruding into the donut space between the firing pin and the bolt's firing pin hole. Perhaps Ruger fixed this with their replacement bolt either having a fatter firing pin, or the hole in the bolt has a smaller diameter (or both). Or it could be you are shooting milder loads, or using a different type of primer.

It's probably a faulty extractor claw, but could also be the reloaded cases are getting fatter each time and sticking (fixed by full length sizing every now and then).

Klem


Ref: Grendel blueprint.