quote:

Originally posted by eagle27:
I support OMG's thinking, there is not a lot you can improve for accuracy of good 22RF ammunition. Quality control of bullets, crimping and powder charge seem to have been well sorted and nothing to be done outside of the factory. Ditto with priming EXCEPT it is possible to improve this area with the design of the rifle.

When we compare rimfire priming with centrefire, the rimfire is pretty primitive. Centrefire primers have a centralised anvil and receive a solid blow from the firing pin igniting the priming mixture in the centre with the mixture being consumed evenly from centre to outside circumference of primer cup and the brisance of the burn directed to the powder charge though the central flash hole.

The rimfire on the other hand receives a firing pin blow of various weights and profiles to only one small part of the rim. There is no flash hole separating the powder from the priming mix therefore as the priming mix ignites at that one point the powder is also ignited at the same point.

The distribution of the priming mix around the rim of rimfire cases is often not very even, better for specific target ammo through better quality control of the process.

Any improvements to the firing pin blow should result in better primer ignition and better accuracy.

The Gevarm 22RF semiauto that fires from an open breach, I think proves this. There is no firing pin, just a raised ridge across the breach block which gives a heavy blow diagonally across the head of the the rimfire case creating detonation at two points on the rim. Despite the heavy breach block slamming forward, driving a cartridge from the magazine into battery in the chamber and detonating the primer, all on the release of the trigger, these rifles are very accurate with good ammo.

Would be interesting if rimfire priming was ignited by a blow to the rim of the case around it's entire circumference?

Priming ignition from a Gevarm rifle

quote:

Originally posted by Saeed:
I have no idea how many 22 rim fire I have shot, probably more than most people do.

These include every single type I could get.

From the extremely expensive target types, to very cheap ones from China.

The rifle I am using for this test from Bleiker.

Bleiker

It is without question the most accurate 22 I have shot.

I am getting very small groups.

The rifle has a tight chamber.

Some ammo is very hard to chamber.

I am using the same lot of ammo for my test.

As from previous experience, 22 rim fire ammo is most definitely NOT 100% consistent.

I have a 25x scope on it.

One group would hard to measure, and next is no where near as good.

I am about half way through.

Telling a friend about some of the results, and finds them very strange.

quote:

Originally posted by carpetman1:
[QUOTE]I have no idea how many 22 rim fire I have shot, probably more than most people do.

These include every single type I could get.

From the extremely expensive target types, to very cheap ones from China.

The rifle I am using for this test from Bleiker.-


Was that a typo? Is it a Blaser?

quote:

And I never like to miss an opportunity to put the Blaser in the spotlight!