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I have seen some bolt action rifles with bolt lugs that are in different planes. For example a 4 lug bolt with one pair of lugs in front of the other, each pair 180 degrees apart and a corresponding 90 degree bolt throw. The standard Remington 700 has 2 lugs 180 degrees apart with a 90 degree bolt throw. The rear of the bolt lugs engage the front of the action lugs and they interface in one plane. With todays manufacturing precision , is it easy to achieve 2 pairs of lugs (a 4 lug bolt) with both pair engaging the action lugs simultaneously? I am seeing some amazing performance claims from multiple plane bolt interface setups. Is it just that one pair of lugs really sets the bolt head position or are all 4 engaging at the same time? I guess someone could apply sharpie marker and see what gets rubbed off? This is really a question about machining tolerances and how this might impact performance, wear etc. Thanks
 

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Theoretically the number of lugs should not have an effect on accuracy as their function is to restrain the bolt thrust along the axis of the barrel. It is possible in any case that one or more lugs do not engage properly which increases the load on the remaining lugs and can cause some minor bolt torquing. Does this affect accuracy? It is assumed that it may and one of the actions done when blueprinting actions is to ensure proper engagement of all lugs.

A three or four lug receiver is going to cost more to manufacture and will require more work to insure that the lugs share the load so its likely that a three or four bolt custom action is probably tied to a higher quality barrel and will likely be more accurate. Hence your observation. Has someone proven that one design is more accurate due solely to the number of lugs? Maybe, but I'm not aware of such a study.
 

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Theoretically the number of lugs should not have an effect on accuracy as their function is to restrain the bolt thrust along the axis of the barrel. It is possible in any case that one or more lugs do not engage properly which increases the load on the remaining lugs and can cause some minor bolt torquing. Does this affect accuracy? It is assumed that it may and one of the actions done when blueprinting actions is to ensure proper engagement of all lugs.

A three or four lug receiver is going to cost more to manufacture and will require more work to insure that the lugs share the load so its likely that a three or four bolt custom action is probably tied to a higher quality barrel and will likely be more accurate. Hence your observation. Has someone proven that one design is more accurate due solely to the number of lugs? Maybe, but I'm not aware of such a study.
I have never seen a 4 bolt receiver so I'm thinking what looks like 4 lugs is a two lug bolt with a set of lugs for cocking the rifle when the bolt lever is down.
 
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