PMC ammo & 10/22 problems

[RugersGR8]

Has anyone had problems when shooting PMC ammo(Sidewinder and Zapper) in their 10/22's? It seems that the PMC rim thickness is less than on other brands of ammo that I have measured with a caliper. I took my bolt out of the gun and got the rim thickness on it down to about .045". My understanding is that the industry standard for .22 ammo is .042". That leaves me about .003" play so that I will not have a slam fire. I've gotten better firing pin impressions/dents since I've done this on other brands of ammo, but the PMC is still giving me light hits and failure to fire(FTF'S). Also the PMC seems to have some waxy type of bullet lubricant. However, this same ammo seems to work well in a 77/22 . Everything that I have seen on the web and read in magazines speaks well of PMC's accuracy for the most part. Anyone else have any input??

[hubmonkey]

I have used some PMC Scorematser with decent success. I have found that shooting many 10/22's that they are pretty fickle on what ammo they shoot reliably. The best thing to do is buy small amounts of many types of ammo. Shoot then clean shoot then clean. This will help you determine what ammo YOUR 10/22 likes.

One thing you may also try is the way you clean and maintain the gun. Something that has been pretty helpful for my custom 10/22 is not using oils to lubricate it. I clean it free of all oils and use Remington Dry Lube. This helps keep dirty .22 ammo from sticking.

A couple of types of ammo I would try for your application is...

CCI Blazer.. I use this alot and is pretty good stuff for cheapo.
Winchester Dynapoints.. Copper washed, cheap (9 bucks for 500), and pretty consistant, for bulk ammo anyways.


Hub

[RugersGR8]

Thanks for the info. I usually try several brands for reliablity/accuracy. Winchester Super X and Dynapoints, Federal and Remington bulk pack, and CCI all give good reliability. Usually Winchester and Federal give me better accuracy.

As far as lubrication, I use a diabetic syringe to apply very small amouts of Breakfree, MilTec or other lubes. I agree that less is better on that score.

Getting back to the rim thickness on the PMC, I measure both Zapper and Sidewinder and they went down as far as .039". Most of the other ammo that I measure ran between .041" and .043" fairly consistently. I didn't measure a large number of rounds, so I couldn't say that the results that I found would be the general rule for all such ammo.