BSA Martini Conversion
- Thread starter Tack
- Start date
Some material off the 'ears' of the lever, to drop the height that the breech block lifts on closing the action. This aligns the firing pin to center of bore.
The extractor will have to be replaced or modified to fit the hornet Rim. Not a really complicated part to make if you have any talent with a hacksaw and files.
Many of the guys that have done these conversions have dovetailed in a new face onto the breech block. This is for two reasons. One is that it provides a 'bushing' for the slightly smaller firing pin diameter desired for the higher pressure cartridge, and second, it provides some material to shape so that the face of the breech block is square to the bore again.
Have read of guys just reshaping the breech face, but have read that it is not the preferred method. If left as-is, the breech face will be at a very slight angle, and will cause the brass to get out of shape when shot. Not a huge deal if you don't expect much out of your rifle, but if yer gonna go through the trouble....
Cheers
Trev
The extractor will have to be replaced or modified to fit the hornet Rim. Not a really complicated part to make if you have any talent with a hacksaw and files.
Many of the guys that have done these conversions have dovetailed in a new face onto the breech block. This is for two reasons. One is that it provides a 'bushing' for the slightly smaller firing pin diameter desired for the higher pressure cartridge, and second, it provides some material to shape so that the face of the breech block is square to the bore again.
Have read of guys just reshaping the breech face, but have read that it is not the preferred method. If left as-is, the breech face will be at a very slight angle, and will cause the brass to get out of shape when shot. Not a huge deal if you don't expect much out of your rifle, but if yer gonna go through the trouble....
Cheers
Trev
Mine came without anything else attached. I sure would not consider stripping a decent original to make a project out of.
I think mine's gonna become a Hornet, to start with.
I like the feel of the originals. Not exactly "walking around" rifles, though.
Cheers
Trev
I think mine's gonna become a Hornet, to start with.
I like the feel of the originals. Not exactly "walking around" rifles, though.
Cheers
Trev
Martini action
Large action or small?
Go to www.martinihenry.com for more info and go from there - there are sites that tell how to properly adjust the height of the breech block without creating scrap metal parts that are hard/impossible to replace.
Large action or small?
Go to www.martinihenry.com for more info and go from there - there are sites that tell how to properly adjust the height of the breech block without creating scrap metal parts that are hard/impossible to replace.
BigUglyMan
CGN Ultra frequent flyer
- Location
- New Scotland
What kind of condition is it? Might be smarter to sell it and buy a proper 22 Hornet.
I haven't done any for many years and don't do them any more... they were a pain to do no matter what way you did them.
I preferred welding the firing pin hole and re drilling for the center fire location and then altering the firing pin itself.
Fitting the extractor was always a bit of a chore and no matter what you did the fired cases always appeared large due to the under size brass that is manufactured. I don't know why but 22 Hornet brass is considerably under saami specs.
Then the problem of mounting a scope so you can effectively load and unload... usually has to be fairly high.
I preferred welding the firing pin hole and re drilling for the center fire location and then altering the firing pin itself.
Fitting the extractor was always a bit of a chore and no matter what you did the fired cases always appeared large due to the under size brass that is manufactured. I don't know why but 22 Hornet brass is considerably under saami specs.
Then the problem of mounting a scope so you can effectively load and unload... usually has to be fairly high.
- Location
- Peace River, Alberta
I am thinking of this..
But have gone the route of trying to go to a bigger caliber such as one of the 17 centrefires, or a 204, or 221 Fireball.
Still trying to figure out if this is going to work.
Greg
But have gone the route of trying to go to a bigger caliber such as one of the 17 centrefires, or a 204, or 221 Fireball.
Still trying to figure out if this is going to work.
Greg
Rimless extractors have been made to work, but are another minor PITA.
Dig around the web and there are pictures out there. Salient feature is an elongated hole for the cross pin so the extractor can slide over the rim, and a spring to push the extractor back under the rim when it does.
Cheers
Trev
Dig around the web and there are pictures out there. Salient feature is an elongated hole for the cross pin so the extractor can slide over the rim, and a spring to push the extractor back under the rim when it does.
Cheers
Trev
The Brits liked to mark their bore sizes by the smaller bore diameter. The US convention was to mark them by the diameter at the grooves.
Their designation for the .22LR was .220 Long rifle. Take a .220 bore, drag a rifling cutter through it for .0015 to .002 per side, and you are at .223", or .224".
Still not a bad idea to slug it, though. Best to know what size it actually is, as it'll help when it comes time to look at reamers.
Pilots on the 22 centerfire reamers are listed at .219, more or less (by tenths of a thou).
A CF barrel, these days is .224, mainly. CZ is still making Hornets on .223 barrels, if James Calhoons website is to be beleived, and there have been lots of CF wildcats made on Rimfire barrels. Downside of a rimfire barrel is the twist rate is typically 16" (20" for .22 Short) and will not stabilize heavier bullet well. Rimfire barrels are typically made of somewhat softer steel, as well.
Light bullets and light loads, though, and rimfire barrels have held up pretty well in practice.
A BSA rimfire barrel is worth enough to be not worth considering as a prospect for a rechamber anyway, though. Barrel blanks are cheap enough. If it's already butchered <shrug> owners choice!
Cheers
Trev
Their designation for the .22LR was .220 Long rifle. Take a .220 bore, drag a rifling cutter through it for .0015 to .002 per side, and you are at .223", or .224".
Still not a bad idea to slug it, though. Best to know what size it actually is, as it'll help when it comes time to look at reamers.
Pilots on the 22 centerfire reamers are listed at .219, more or less (by tenths of a thou).
A CF barrel, these days is .224, mainly. CZ is still making Hornets on .223 barrels, if James Calhoons website is to be beleived, and there have been lots of CF wildcats made on Rimfire barrels. Downside of a rimfire barrel is the twist rate is typically 16" (20" for .22 Short) and will not stabilize heavier bullet well. Rimfire barrels are typically made of somewhat softer steel, as well.
Light bullets and light loads, though, and rimfire barrels have held up pretty well in practice.
A BSA rimfire barrel is worth enough to be not worth considering as a prospect for a rechamber anyway, though. Barrel blanks are cheap enough. If it's already butchered <shrug> owners choice!
Cheers
Trev
- Location
- Peace River, Alberta
Some one help me out!!!
I have been looking and looking and looking for a gunsmith in Canada that can help me with a rimless conversion on a Martini BSA model 12 or 13. However I just can't seem to find anyone to help me or that has the knowledge or experience doing this conversion already.
I have found a couple gunsmiths south of the border that have the ability but that route is a major pain in the butt trying to go that way.
Someone please point me in the right direction.
Thanks guys.
Greg
I have been looking and looking and looking for a gunsmith in Canada that can help me with a rimless conversion on a Martini BSA model 12 or 13. However I just can't seem to find anyone to help me or that has the knowledge or experience doing this conversion already.
I have found a couple gunsmiths south of the border that have the ability but that route is a major pain in the butt trying to go that way.
Someone please point me in the right direction.
Thanks guys.
Greg
