View Single Post
  #2  
Old 10-04-2017, 04:18 PM
mhb mhb is offline
 
Join Date: Jan 2014
Location: S.E. Arizona
Posts: 243
Default It is a nice looking target rifle...

But you need to be cautious about the proper ammunition. The actual chambering does not seem to be marked on the barrel, and the ammunition and dies which you got with the rifle MAY be correct for it, but the first thing you should do is make a chamber cast to verify the dimensions of the chamber. You need to know that the Mann chamber (named after rifle ballistics experimenter Dr. Franklin W. Mann) is made with a very tight neck - so much so that it probably would not accept factory loaded ammunition - and the cases for use in a Mann chamber were neck turned so that the diameter of the neck of the loaded cartridge is as near to the actual neck diameter of the chamber as possible - there is very little if any clearance at that point to permit expansion of the neck when the round is fired, with the purpose of keeping the bullet as closely aligned with the throat and origin of the rifling as possible. This condition results in very high pressures if standard loads are used, so caution must be exercised in working-up loads for use in a rifle so-chambered.
There is no evidence that the tight neck produces better accuracy than an otherwise excellent chamber suitable for cartridges of standard factory dimensions.
If you intend to shoot the rifle, and don't want to go to the extra work of preparing proper ammunition for the Mann chamber (asuming that the chamber actually does still have the tight neck), you might wish to have the chamber altered to factory spec. - this might be accomplished by simply reaming the neck of the chamber, but the chamber cast is the only way to determine exactly what the dimensions of the chamber currently are, and how best to proceed.

mhb - MIke
__________________
Sancho! My armor!
Reply With Quote