what's the barrel contoue for the Marine M40A1

I found this on one The Firing line Forums posted by a member who is in the know when it come to Sniper type rifles......

The M40A1 barrels are 24" long and are about a #7 contour ending at about .900 at the muzzle. Twist rate is 1 in 12".
I am pretty sure it is a #7 contour..........

Also......

For the M40A1.....This info was given to another shooter from Gary Schneider of Schneider barrels:

The M40A1 barrel dimensions were 1.10-1.210 +/- X4", straight tapering to .890-.910 +/- @ 26.5".

After cutting and threading the breach end you would end up with 1.20" X3", +/-.
Once it was threaded at the breech end they(the USMC armorers I believe) would trim the muzzle of the barrel to 24" from the front of the trued recoil lug, as is their method of measurement, making the muzzle approximately .920-.940, again +/- .
He stated there were variations of +/-.015", maybe more at times.


SKBY.
 
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This is generally called an MTU contour: Marksmanship Training Unit. The disadvantage is the lack of meat at the shank which makes setting back difficult.
 
This is generally called an MTU contour: Marksmanship Training Unit. The disadvantage is the lack of meat at the shank which makes setting back difficult.

Yup!....But it looks old school cool! ;)

Sounds like a neat project marlink!

If I ever build another 308 I'd like one just like it ....Wood stock and all!
 
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