French Mas-36 oversized chamber?

[glshop20]

Does anyone have any experience with this rifle?  I recently picked one up for a good price and it appears to be brand new.  It shoots well and I am working up reloads for it.  The new brass was quite difficult to size and the fired brass more so.  I had to polish out the size die so that it did not take a crazy amount of force to do a partial size. This was not a concern since this is the only rifle I have in this caliber.  Do the chambers tend to run oversized?  Any input would be helpful.   Thanks,  Walt

[R.W.Dale]

 I've owned a couple MAS36'es and all had fairly tight chambers. What is your load and what brass are you using?  I bought some FNM 170grn factory loads to reload the brass. But apoun firing this junk ammo would stretch and bulge the cases like crazy! Making them almost impossible to resize. I have had no such problem with reloads or even the lighter FNM loading.


 Have you taken measurements of a RESIZED once fired case and compared the to the cartridge specs?
 I've used Lee dies to load 7.5 French and mine work OK but as with all lee equipment all bets are off. I would suspect the dies as much as I would the rifles chamber. Now days I use my 7.62x54R sizing die with a .308 expander ball to ONLY NECK SIZE my 7.5x54 brass before loading in an attempt to extend brass life. The reason for this is a 7.62 Russian die backed out a couple of threads won't touch a piece of 7.5MAS brass anywhere other than the neck.

[glshop20]

I recently loaded some neck- partial sized cases and will see what happens.  I tried to see if I could neck size with other dies but the brass would not go in far enough. I believe I have Graf brass and the necks appear to be annealed.  I am loading 150gr. Hornady  fmj-bt with 42 grs. Imr 4064.

[S.S.]

Those have been modified to shoot several different calibers by importers
if I remember correctly... Especially 7.62x51. You may have one of those.
I think 7.5 Swiss was tried also.

[R.W.Dale]

Especially 7.62x51

 A 7.62 NATO or 308 chamber wouldn't even come close to accepting a 7.5 MAS cartridge.

[1911crazy]

I would checkout the headspace first.

My century mas 36 ufixem came with a brand new 308win barrel and the headspace is way beyond what it should be.  Someone was sleeping with the chamber reamer.  Its on my fix'm list sometime during the winter when i get a chance what year who knows.

[S.S.]

My point was that it could have been an odd caliber, not any one particular caliber..
If importers in the U.S. change to popular calibers here. Importers in other countries
would surely try to change them to popular calibers there. Could be anything,
Do a chamber cast and find out..

[1911crazy]

Sumner your right the 7,5mm bore is interchangable with the 30cal bore too the bullets are the samey same 308" diameter.  The 7,5mm french,  308win/nato and the 7,5swiss are all related bullet wise.(projectile diameter)  It can be rechambered to anything in 30cal. anything odd ball too.

I have heard that the 7,62 nato chambers are different than the 308 win chambers, meaning the headspace specs are different.  I'm not willing to shoot my MAS36 in 308 until i'm sure its safe to shoot but right now it won't pass the field  headspace gage in 308win.