Bolt shims

Dave64

Dave64

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Well once again in the pursuit of accuracy I’ve tripped across another which could be as good as it sounds internet finding a company called www.triggershims.com out of Jackson Mississippi owner lance Shively which has a variety of accuracy improvement items that could potentially be worth a try along with a lot of other cool stuff.
The one item that I’ve placed a order on was the bolt shim kits now 170.00 doesn’t buy a whole lot of machinists shims but what I did order was a few packs of what is pretty popular ie cz457 452 453 and brno along with picked up some bergara b14R and tika rimfire bolt shims and they have a whack more, the kit basically is tightening up the head space only ones I’ll be keeping would be the 1 brno and 1 457 pack the rest I’m going to share who ever shows interest I’m not into making any extra coin I’ll sell for what I picked them up for I don’t have a lot saying that first come first serve look them up definitely shows potential.
Tons of helpful videos the stuff makes sense and if one can tighten groups up could very well be worth a try!
Just a share for what its worth to my rimfire fellow fanatics.
Peace out!
 
I’ll mark you down for the first ones when I receive them I’ll send a copy of my bill for actual costs you can emt me for just the one pack I’ll throw them in the mail.
 
That makes sense when the rimfire headspaces off the mouth. Firing pin protrusion and extractor tolerance is always loose.

A while ago I was commuting an hour each way twice a day, and on car-pool weeks, I could read or sleep. I remember seeing a cartridge gauge in the Champions Choice catalogue that measured .22 LR rim thicknesses. It was a wedge gauge that the shooter dropped a live round into a hole and moved a slider over the rim. The idea was to find rounds that were outliers and had thicker or thinner rims than the standard deviation. In any box of 50 there will be a measurable variation - probably very slight but with practise something discernable. If your self-coaching positive talk is, I only shoot perfect shots, having that preparation step to find only "perfect" ammo will be part of your version of success.
 
My old coach had lent me a thickness gauge to play it... After trying it sorting a brick of T22 and another brick of RWS Target (the old grey and red box), my uneducated conclusion was that I couldn't discern any difference between the sorted/unsorted ammo... and my time could be better spent building upper body strength (and saving the $ for better ammo)...
- I'm not a benchrest shooter by any stretch of the imagination.

Rimfire-accuracy-gauge-2-1024x352.jpg
 
There's a lot of info about this on other forums like RFAccuracy, SnipersHide, etc., worth reading details. Some rifles can benefit from tightening the headspace, 'pends on your usage. An interesting topic, at the least.
And way more valid than thickness, weight, et al. When a bolt is indexed off the locking slot of the receiver as opposed to lugs there can be a lot of 'variances' in headspace that can be adjusted with shims.
 
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The application don’t apply to world class shooting only to help the mass production rifles …most accurate rifles headspace has a lot more attention given to the build.
But if ya can make your 800.00 unit shoot like a 2000.00 unit it’s a cheap investment.
 
Headspacing is not a key reason for shortcomings in .22LR accuracy performance, in either world class rifles or budget-minded models. The main factors in rifle performance are barrel/bore quality and ammo selection. In mass produced factory rifles with good ammo, barrel characteristics are always the most important in determining how the rifle shoots. Regardless of headspace, an $800 rifle is unlikely to perform like one costing 2.5 times as much. Barrel quality matters more.

Noted .22LR benchrest rifle builder Bill Calfee has said in his book and elsewhere that as long as headspacing is safe, it's not very relevant to accuracy performance. Calfee and most other .22LR custom rifle builders use the SAAMI and CIP specification of .043" as the headspace dimension. All match ammo is produced with SAAMI and CIP specs in mind.
 
sillymike said:
My old coach had lent me a thickness gauge to play it... After trying it sorting a brick of T22 and another brick of RWS Target (the old grey and red box), my uneducated conclusion was that I couldn't discern any difference between the sorted/unsorted ammo... and my time could be better spent building upper body strength (and saving the $ for better ammo)...
- I'm not a benchrest shooter by any stretch of the imagination.

Rimfire-accuracy-gauge-2-1024x352.jpg
Click to expand...
Possibly watering the lawn would time better spent
I love the over the top tech winnies knock yourselves out
 
sillymike said:
Then again, the mental game is a big part of shooting... So if you believe in something, it will probably help you.
- Used to have a lucky hat... and I got pretty distraught when I lost it...
Click to expand...

What is it worth to have that hat back? I know people. HAHA very good point made. Faith is something very powerful over the mind.
 
Just to satisfy my own curiosity, I took my B14R headspace from the factory setting of 047 to 043 with a set of Triggershims from the USA. I also fitted a Crossroads Precision Rifles (Texas) steel bolt shroud and "light" striker spring at the same time. This rifle shot well from the get go but with the right lot numbers of ammo, it is now serious competition for both my Vudoos.
I used the shims to take the headspace on an unmodified Lithgow LA101 from 045 to 043 - Couldn't see any difference.
My observation only so not really convinced either way. I do have all my rim fire builds headspaced to 043. I use SK/Lapua exclusively.
 
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