Need shims for 40x bolt

The "shim" is nothing more than a flat washer, Joe Cowan sold a set(5 or 6?) in 0.001" increments, made of brass; they are exact ID and OD in size to fit. The shim/washer goes between the bolt handle and the bolt body, and would disrupt this, already set from years of use, wear point. It's like a domino effect, this off-kilter wear point then affects the locking lug wear point, and so on. Don't forget, we're talking about old 40x's, or old 52D's, that have the wear points set. If you had brand new bolt/receiver, it wouldn't be an issue, but then again, in that case, you wouldn't have the need to correct headspace. Thanks, Douglas
 
To Douglas

Thanks, I think I understand what you are saying. The bolt would be thrown "off-kilter" by a variation in shim thickness. I didn't know the shims varied that much, I would have thought they had nearly parallel sides. I was thinking about using a shim in a 52 but I think I'll reconsider.
 
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Take a set

Just like the FP spring will take a set after a year or so, the same this happens with the bolt assembly. The mating surfaces of the bolt handle/bolt body, will develop a wear pattern over the years, and the locking lugs will also developer a similar contact pattern. When you introduce a material that will disrupt that patten at one end, you will in affect disturb one of the other related patterns. That's one of the main reason that using shims to adjust HS is not recommended. The hard and fast rule, that HS affects ignition, has been a subject of discussion for years, and no one has proven to me, that it has to be a set number such as .042". I have Suhl's, Winchester 52 c & D's as well as a Hall, and they all have different HS measurements. When I'm on, they are as well, so the shooter needs to take some of the heat instead of blaming HS. IMHO, a HS of anything between, .039" to .050" will suffice.
 
I thought everyone, including Calfee, believes that excess head space has a bad effect on ignition and thus accuracy. Basically the position of the case can affect the firing pin strike. Has this "theory" now been disproved?

To Fred J, I think the comparison between a firing pin taking a set and a bolt changing its wear surfaces might be a little bit off. Coil springs are under very high stress and may tend to "relax" but bolt wear surfaces are probably loaded to about 1/100 the spring stress for about 1/1000 the time. I'm probably wrong as I'm often accused of being but I just don't think bolt lugs will show much of a significant "wear pattern" over the years. There's a pattern there but it can probably be measured in millionths of an inch! I believe the change that might occur in a bolt by adding a shim would only happen if the shim varied in thickness by several thousandths.
 
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