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Grampa
December 27, 2001, 02:32 PM
I have a Ruger P94 40 cal. that occasionally jams. This is with both handloads (180 gr. Rainier FP with 6.8 gr. Accurate #5) and factory 180 gr. CCI Blazers. It may fail to extract or feed properly once in every 20 rounds, and I haven't been able to trace it to a specific magazine. All rounds are seated to 1.12".

Usually the fired case is only partly extracted from the chamber, however, I had a few instances where the next round from the magazine was jammed at an angle against the top of the chamber. The extractor looks good and tight.

This week I gave it a very good cleaning (I usually clean after each session)and got out my trusty rotary tool and polished the feed ramp and the top of the mouth of the chamber, without going into the chamber. I'm loading up some more rounds, and will test it out on Saturday.

While polishing the feed ramp, I noticed the chamber has a satin finish. Is there a reason NOT to polish inside the chamber? Do the Ruger engineers leave this with a satin finish specifically to retain the just-fired brass for a millisecond?

zot
December 27, 2001, 03:34 PM
you might get split cases polishing chamber,I don't trust the .40
too many stories of case rupture,

James K
December 27, 2001, 11:17 PM
You can do some polishing inside a chamber, but somehow, a rough chamber doesn't sound like the problem. Are the cases marred by bright rings or are there other indications of a scored chamber?

One possible cause of feed failure is a rough breech face or some sharp surface that does not allow the case head to move up on the breech face. Sometimes, a too tight extractor or one with a sharp edge that digs into the case can be the cause.

Make up some dummy rounds with no powder or primer and work them through the action slowly by hand and see what happens.

Good luck,

Jim

Grampa
December 30, 2001, 12:31 AM
Well, polishing the feed ramp didn't help. I fired about 60 rounds through it today, and had 6-7 jams. All of the jams this time were caused by the fired casing not getting pulled completely from the chamber.

Jim -- No, no other real prominent markings on the fired cases. And I was using a variety of mags. I'll make up some dummy rounds and see if I can spot the problem.

Otherwise, I guess it's time to call Ruger.

Eric Larsen
December 30, 2001, 11:12 AM
I had intermitten problems with my barrel/slide interference.
My barrel was rubbing on my slide do to a crown on the front lug.
It caused FTF problems...just enough that I didnt carry my gun for a little while.
Usually a FTE is one problem and a FTF is another. The one characteristic that ties both togethor is proper slide movement.
Just a thought...check you fit and finish on all mating parts...wont
hurt...shoot well

Grampa
December 30, 2001, 04:41 PM
Hi Eric-

I field stripped the pistol last night and inspected it as I cleaned it. I didn't see any unusual wear marks that I don't see on my P95 or recall on my 9MM P94. I did remove the ejector last night and cleaned some gunk from behind it. I wouldn't have expected that to make a difference. Maybe I'll get out this afternoon for a bit and fire off another 50 rounds.

Thanks

George Stringer
December 31, 2001, 09:27 AM
Grandpa, I think you have an bad extractor or one that needs adjustment. You can bend the tail slightly sort of like with a 1911 and increase the tension. Also you might try deepening the hook a little. George