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Mike, further to our discussion regarding case rim size for the 6.5x53R case. Rolland sent me a copy of an older edition of Handloader Magazine where the author David Webb goes into some detail as regards to rim thickness (Maybe Rolland could post the article for us). What is interesting is that there were actually two different rim thicknesses, 0.060" for the Dutch Mannlicher rifle and 0.075" for the Romanian Mannlicher rifle. Both of these cartridges had different case designations from DWM and Roth.

Also of interest is some information that I have from a very rare book written by some Dutch authors on the M1895 Dutch rifles and the cartridges that the dutch army used. It is written in Dutch and English and some very interesting photos and drawings although unfortunately most of the dimensions on the drawings of the cartridges are basically unreadable. During their time there were two case profiles, a 1910 and a 1915 and early cases used a rounded head which was changed later on to a flat head as the rounded head was prone to gas leaks if a primer was pierced.

Now here is the interesting bit, These original production drawings show both the rims of both the 1910 and the 1915 profile to be 0.051" thick with a tolerance of +0.004".

So which is correct and what is correct and who is correct. The military brass that I have has a rim of 0.063" and yet the original drawings (They look like a scan of a microfiche drawing) show 0.051" to 0.055" which is actually closer to the Buffalo Arms claim.

However herein lies the problem in that none of my three Mannlicher rifles have headspace that is remotely acceptable even with the Kynoch brass. Two are 0.0018" and one is 0.014", and to make matters worse on one rifle, the Gibbs,(I haven't done this check yet with the other two rifles) the counter bore for the rim in the back of the barrel is o.o73" deep meaning even if the bolt head were to touch against the back of the barrel there would still be 0.010" headspace. This of course means that the only way that you can get good case life is to re-form the brass and bring the shoulder forward so that they headspace on the shoulder rather than the rim. Which is something that you can not do if you have factory ammo which I do and want to use.

I strongly believe that the reputation Kynoch had for case head separation and splits had nothing to do with the quality of the brass but instead was a victim of excessive headspace, for when I fire the the same Kynoch factory ammo with 0.014" of packing tape on the head, the cases are perfect with zero thinning when measured afterwards, even though the brass wall thickness is 0.010" thinner than my 338 Win Mag Winchester Brass.

The one thing that we can be sure about in regards to 6.5x53R ammo and the associated rifles is that nothing is set in stone and everything need to be checked before shooting.

Matt.

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