Bolt shims are not specifically addressed in Section 5.
"Accessories to the rifle" are acceptable as per Section 5.B.3.a. This includes aftermarket triggers, extended magazine releases, barrel tuners, etc.

I would think bolt shims would fit the spirit and intent of "accessories to the rifle", but the final call comes down to the match director.

 

If the bolt is not too easy to lock in factory settings, so you have to use a medium consistent force, then there is no real need for the bolt shims.
I tried the shims on my MTR and even at the lowest thickness I had trouble locking the bolt.
IMHO: If you combine the match chamber of the MTR with match grade ammo, you don't need shims.

 

I tried the shims on my MTR and even at the lowest thickness I had trouble locking the bolt.

What ammo did you see this with? My stock MTR has an issue where it takes significantly more effort to lock the bolt with Eley Team/Match/Tenex, but not with any other ammo.

 

If it is REALLY hard to lock the bolt, you would need a barrel shim.

 

So I run bolt shims on my MTR does it improve accuracy. I think my Eley Tenex is shooting better atleast groups were a bit smaller. But that may have nothing to do with the shims. It could have been conditions,or that day tenex was my first group not the 14th box of test ammo saved for last on initial test. At 100 degrees after that day i was tired by time I shot the last groups.

Since shim installation I have only tried Eley Tenex, RWS R50 and RWS Special match. All so far shoots well with Special match edging all others out. So I have not done enough testing to say it improves accuracy. Also depending on what your shooting head spacing may not be needed. Measure the ammo rim thickness on aeveral rounds from the lot your shooting. If you have a tolerance too close you may find ammo that will be hard to close your bolt on. You dont want that in competition.

With triggershims.com you will get a set of shims so select wisely if you do go that route. So would i have shimmed if I was to do it again, for me yes.

 

What ammo did you see this with?

I use SK-Long Range-Match and Lapua-Center-X. These fit very well with the MTR match chamber.

 

 

So these are the results after measuring everything. I needed to go with a .002” shim. Groups 1 and 3 were pretty consistent with how it shot prior to the bolt shim. The rest did show improvement and consistency. Gonna do some more testing next week and gather more data before I make my final decision.

All groups were shot at 50yds prone with OG Game Changer as a rear bag