i built a Bren and run it in 303 & 54R.... & 8mm mauser
works perfectly still after THOUSANDS of rounds.
its really easy to have this in a DUAL or TRIPLE caliber set up and then the gun is worth a good deal MORE.... not less.
you get a spare barrel & bolt... there are plenty of these around, have it chambered in 54r. simple as that. you can do it yourself if you have a reamer or Troy at Barrlexchange will do it and the bolt for $75.
for mine and even Trenches & JoeH's guns we have a different bolt for each caliber fitted to the same carrier and headspaced out.
you CAN use the 303 mag on the 54R but it doesnt feed well over 10ish rounds... so you go to mg34.com and get you a mag for 8x56R ($20) and it works fine on the 54R.
depending on your build style and method you can use several settings on the gas regulator. ive got mine tuned to 1 setting for 54R & another for 303 & yet the 3rd for 8mm mauser.
you hear all these stories on chamber verses rifling and so on...
the 303 is 303 and it works perfectly.
the 54R gives you a double neck on the case & isnt good for reloading, but who reloads surplus anyway? it always extracts and runs like a top. the barrel specs are well with in the range for this round...
the 8mm barrel is exactly that. again it was made that way and there is no issue at all.
build your gun, take all the correct build steps & then enjoy shooting multi calibers like the rest of us do.
the hobby is full of people who tell you "you cant". THATS WHY MOST OF US DO!!
here it is in 303 before the finish coat...
and here it is in 54R
only problem i have is not remembering which i shot last, so had to stamp the bottom of the barrels and bolt heads to match.
its easy to tell them apart after you take the bolt out... but just sitting in the vault sometimes the memory gets foggy of what got shot last.
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