Chiappa 1886 to 348 win conversion, questions

[Bleachedtech903]

Yes, I know, just buy an original or browning model 71. Now that that's out of the way.
First, parts compatability, since chiappa 1886 is pretty much an exact copy to the originals, except for threads, I would assume an original model 71 bolt would fit, but would a browning 71 bolt fit is the question.
Then a 348 carrier is needed, again would a browning 71 one fit?
I have better access to browning 71 carriers, than an original, same for the bolt.
A 348 to 45-70 conversion needs just a carrier change, tho the cases get thrown out top of action from the oversized cartridge guides, and oal is weird for cycling.
From this I would assume a cartridge guide change is needed, going from smaller 45-70 rim to wider 348 rim.
So, how much parts would I really need to replace, and fit. Bolt, and carrier guaranteed, and maybe much more.
So, is there anyone with some knowledge that could help?
Again, this just sounds like a fun idea to me, not going for economical, just opening my horizon to interesting avenues of my final goal, a 348 win. Tho I was contemplating a 33 wcf, with a simple barrel swap, but wheres the fun in that.

[John Taylor]

The bolt and locking lugs of the 71 are different from the 1886, there is a slant where the locking lugs fit the bolt to make it easier to open.

[indian joe]

Yes, I know, just buy an original or browning model 71. Now that that's out of the way.
First, parts compatability, since chiappa 1886 is pretty much an exact copy to the originals, except for threads, I would assume an original model 71 bolt would fit, but would a browning 71 bolt fit is the question.
Then a 348 carrier is needed, again would a browning 71 one fit?
I have better access to browning 71 carriers, than an original, same for the bolt.
A 348 to 45-70 conversion needs just a carrier change, tho the cases get thrown out top of action from the oversized cartridge guides, and oal is weird for cycling.
From this I would assume a cartridge guide change is needed, going from smaller 45-70 rim to wider 348 rim.
So, how much parts would I really need to replace, and fit. Bolt, and carrier guaranteed, and maybe much more.
So, is there anyone with some knowledge that could help?
Again, this just sounds like a fun idea to me, not going for economical, just opening my horizon to interesting avenues of my final goal, a 348 win. Tho I was contemplating a 33 wcf, with a simple barrel swap, but wheres the fun in that.

I have both rifles here
my Chiappa needed serious work to get it to function at all - the carrier was too small to allow the rim to enter fully

yes a copy of the 86 as far as I can tell - some fellers say parts will interchange with oringinal winchester --- I believe I test swapped bolt and locking lugs and they fitted (3 years ago ? memory ?)

Carrier ? its not the rim! - I measure case rim diameter as exact same (so that there difference is a myth) - WW 348 vs Starline 45/70 --the difference is in the body of the case ahead of the rim - so if one will go in the carrier - tother will also - the lugs on the carrier that hold the case in place (stop it popping up vertical) will be sloppy on the smaller body case

86 has that pesky carrier hook arrangement to elevate the carrier but it is smoother = less effort - at the end of the stroke to do it

without stripping the gun down I am not sure of the 71 mechanism for achieving that but it feels very similar to how a 92 works - a definite click / pop right at the end of the stroke John Taylor would know this bit

I have puzzled long and hard over stories of 450 alaskan conversions stovepiping rounds out the top of the action - looking at my 71 - just cant see how that would happen - the carrier holds the rim firm, there no way that stovepipe could happen unless the round was shorter and didnt go properly home on the carrier in the first part of the cycle -- John might have this story but it has me tricked.

[john.k]

The cartridge guides are the most critical part of Winchester conversions ,and if the correct original parts arent available , then it takes a very experienced person to get the conversion to work first time (or at all)...........this is actually the genius of the Marlin .....there is no need for guides.

[Bleachedtech903]

How hard do you think it would be to enlarge a 45-70 carrier to fit the 348 case? Would it need machined or just a dremel and patience?
Actually, does anyone have an original model 71 or a browning 71 they would be willing to take apart and take pictures of the parts so I can see and understand what the differences are between the 1886 action and 71 action.

[indian joe]

How hard do you think it would be to enlarge a 45-70 carrier to fit the 348 case? Would it need machined or just a dremel and patience?

Back to my earlier reply --the rim diameter from 348 to 45/70 is NOT DIFFERENT - they measure same size so whats to enlarge ??

Actually, does anyone have an original model 71 or a browning 71 they would be willing to take apart and take pictures of the parts so I can see and understand what the differences are between the 1886 action and 71 action.


Maybe for my own curiosity I pull that Browning 71 down some time in the next month or so

[John Taylor]

How hard do you think it would be to enlarge a 45-70 carrier to fit the 348 case? Would it need machined or just a dremel and patience?
Actually, does anyone have an original model 71 or a browning 71 they would be willing to take apart and take pictures of the parts so I can see and understand what the differences are between the 1886 action and 71 action.

The rim size is the same for 45-70 and 348. The ears on the carrier keep the cartridge from stove pipe. If the cartridge is shorter ( like the 50 Alaskan ) then the cartridge is not pushed all the way back into the carrier and can stove pipe when the action is worked fast. When going to the 50-110 the carrier has to be opened up a little because the body of the cartridge is fatter. The carrier has a little hump on the bottom, the rim will go past but the fatter body will not let it go. The 348 has a taper and is not as fat as the 50-110. The 1886 has a part that catches the rim of the cartridge to control it going into the carrier, the 71 does not have this.

[Bleachedtech903]

I found a guy on youtube who converted an original 1886 lightweight 348 win using a mix of original model 71 parts and chiappa parts. Original 71 bolt, lugs, barrel and cartridge guide, then everything else was chiappa.
Also found where one was being sold with excess headspace, but it also seemed to use the original 1886 bolt and lugs. Idk, if using a model 71 bolt and lugs would have helped the rifles action last longer before stretching.