Bolt Bushing Reduces SD!

I in my wildest dreams did not think that Bolt Bushing could help with SD (standard deviation). In my mind it helps immensely with harmonics but not SD. I was wrong however. It seams I have had an overwhelming number of customers tell me that after they had their bolt bushed, they saw a drop in SD. If you do not know what some of the other benefits are to bolt bushing you should check out my other blog post called  What Does Bolt Bushing Acomplish. Below are two testimonies of just how much Bolt Bushing has helped some of my customers.


Sam has a custom Mosin that he could hardly even get to a mild load without blowing primers. His bolt was getting filled with soot and primers fragments too. So he sent me his bolt and I took the hole from a 0.100in and firing pin that was .091 to a much smaller .069 and made the bolt match to that size with proper clearance. Here are his results. Sam tells me his SD dropped significantly too.


Big shout out to Grimstod Desh for all the work on my bolt. Shoots better than ever. 5@200. I’m as happy as a possum on a big green tractor eating grapes.

5 shots at 200y

Sam had to revisit all his loads because of all the new room he had in his rifle now and here is where he finished. Primers are still not flat and now that he does not have any flow around the firing pin he could gain a great deal of MV and accuracy.

“I’m shooting 55gr of bl-c2 under a 168gr bthp and getting 3011 fps average.”



Success Story #2



Another Customer Grindl who takes his Mosin to F-Class matches and even the SWN.

I began having issues with my competition rifle doing weird things . Hang-fires , Non-fire after pulling the trigger and the gun not firing , but the primer dented . And worst of all , it was starting to effect my scoring negatively at a rapid rate .

I contacted Grimstod and sent him my bolt and a extra firing pin to match up , so I’d have a back-up . Turn around time was about six days total and I’ve seen a great improvement in overall performance since the bolt was re-bushed and the F/P turned down .
And like most “F” shooters , I track my scores , and percentages very closely . Since having the bolt done ,on average , I’ve dropped from three “8’s , to one , and my 9’s count has also dropped three or four a string . That means I’ve gained four to six points a string of twenty shots , and over-all my scores have gone up from low 180’s to mid 190’s . And makes this M-N competitive .

So if you’re having firing issues , cratered primers , hang-fires or any of those gremlins and you think the bolt is the problem . Contact Grimstod ….I have been very pleased with the job he did on my bolt / Firing Pin-(s) , and I highly recommend his work . And by way of qualifying my recommendation to any of you guys , I’m a retired master tool & die builder , so I think I can tell good work when I see it . And Grim does good work .



Gene recently send me this update.

“Thought I’d send you a pic of  the results of your work . 100 rounds fired on my 600 yd comp load , which you said I could push harder . I did boost it . From 48.6gr to 53.4gr. Can now shoot the high node & easily 50% more accurate .”


Picture Gene took at the 2018 SWN



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