bolt lift question pertaining to firing pin measurements

[PatrickBruce]

So this is fun.

I have a recently acquired .22-250 axis left hand. This is my 2nd axis, the first is an extensively modified .308, also left-handed. I measured the distance of the cocking indicator (rear of the firing pin) on both rifles from bolt in and locked down (sear holding the cocking piece), vs bolt lifted up (cocking piece on shelf). On my .308, the difference is about .040'', on the .22-250 it's about 0.110''. I took the measurements because I noticed the .22-250's cocking indicator moving so much.

My question is this, is this bad?

I don't think so, the rifle fires with no issue. I know these rifles have issues with over-cocking, clearly this one does. If I try to modify the bolt body to close the distance to about 0.040'', is there any coating or heat treatment I need to do? Also, would you guys try to close the distance to something a bit more reasonable?


BTW, I shot 2 groups with the .22-250 two days ago that were sub 0.5 MOA so the rifle works just fine as is. (I have a picture, just not a paid member anymore, I'll fix that soon :) )

thanks!

Patrick

[J.Baker]

Trust me, you don't want to shorten the bolt body by 0.070". lol All you would likely accomplish is the need to order a replacement bolt body.

Also, the point you're measuring from probably isn't the best place to gauge travel from as you have five parts that could affect said measurements with their tolerances: bolt body length, cocking indicator tail length, rear baffle, bolt handle and the BAS (bolt assembly screw). Let's just say each part has a +/-0.010" tolerance - there's 0.050" right there if they're all on the plus side.

Sometimes it's just best to leave well enough alone when it's working good rather than mess with it and create a headache for yourself.

[Robinhood]

If I am reading your post correctly I am wondering what measurement you are taking. The cocking indicator should move about .200" plus from fired to cocked position. Possibly .235".

[PatrickBruce]

All measurements were taken without firing. Bolt handle down and locked with the sear holding the cocking piece (measurement #1) and bolt lifted up (cocking piece on the little shelf past the ramp).

No measurements were taken with the rifle dry-fired.

When I took the measurements, I subtracted the smaller number (cocking piece on shelf) from the larger (held by sear) to see how much the firing pin is moving.

I'm just surprised that the difference is .070 between the 2 rifles. I was thinking they should be closer.


With regard to tolerances, that makes sense. I was thinking of taking a dremel to the shelf the cocking piece rides on to move the shelf forward. Don't do that?


thanks again.

[charlie b]

I did that to my Axis. I left enough 'hump' to make sure it could not be accidently moved. Only reduced bolt lift effort slightly. Polishing all the surfaces helped a lot more. Didn't change any of the other functions.