reaming a 12g chamber to 3 inch

Evanguy

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I'm wondering who I would contact about reaming my Merkle sxs barrels from 2.75" chamber to a 3" chamber. I got a load of 3" rounds but my favorite shotgun is only 2.75" chambers and was cheap in the first place (Tradeex) so I'm not worried about it not being original and would like the option to use 3" rounds. I'd do it my self but a chamber reamer would be over $300 by the time I got it. Thanks
 
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original, or safe to shoot with the modification is the better question or concern? Without details on the vintage or model of your specific shotgun, pondering the questions about, barrel wall thickness, is there sufficient meat to extend the chambers, increase in recoil and energy, will the receiver withstand, extraction or ejection concerns or problems by increasing the length of the chamber and power of the loads? in looking at some models of Merkel on their web page, there are options for interchangeable barrels?
 
WHY? Your little pile of 3” ammo will be gone quickly, then what? 3” ammo is much more expensive to buy than 2 3/4” and other than for steel shot for which your gun’s barrels and chokes aren’t suitable anyway, offers no advantage. But hey, it’s your gun, if you want to spend the money to make this permanent change to a perfectly decent gun fill your boots. And it appears that you are trying to do it cheap not good so maybe check with Joe the plumber and he can just use his pipe reamer - again.
 
Well i see it as it opens up a few options. Ill be able to fire both 2.75 and 3" with no real down side to it.

I bought a forcing cone reamer last night for $100 and ill be able to do it my self being a manual machinist.

So for $100 my favorite shotgun can now use more types of ammo.

I dont think ill buy any more 3" ammo but i will reload them.

What is the down side to having a 3"chamber in a $400 sxs shotgun that came from tradeex? I was under the inpression most all modren shotguns are 3" and it was a pretty standard size 12g shell.


The gun is a Merkel/suhl it was made in November 1970
 
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Don’t take it personally. You could make a post about the sky being blue and someone on this website would be up in arms.

Anything that makes your shotgun more useful to you is worth it IMO…..whether it’s a perazzi or an H&R
 
TacOrd did this on my WingMaster with a factory 2,3/4, 18" barrel. In my view, this updated the usefulness of the gun. Also swapped-out the receiver ejector/spring to accommodate a 3" shell. Doing one without the other would cause jamming/feeding issues in the Remington 870 platform. Of course, replacing the rivets mean that the receiver should be refinished because it will look ugly if that sort of thing bothers you. So, if you plan a build, this makes sense; otherwise, save your $$$



Edited to include a picture of the work Casey had done:

7vh9cIG.jpg
 
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The scary thing is you can fire a 3 inch 12 gauge shell in any 2 & 3/4 inch chamber... Recoil will be heavier, pattern not as well, but I have not seen a shotgun damaged by doing that... liability wise it would be all on the shooter, using incorrect ammo...
 
Personally I would leave it as is. Increased recoil (and battering of the action), generally worse patterns, perhaps barrel walls too thin anyway, many older doubles are pretty thin. Only reason I could see for 3 inch chambers is waterfowl and then you need chokes and forcing cone suitable for steel shot. Or just sell it and buy one already chambered for 3 inch but it's your gun. And I have seen many shotguns damaged from shooting longer shells than they were designed for. Not to the point of failure just off the face badly and loose. Thinking of old single shots chambered for 2 1/2 inch 12 gauge and 16 and 20 gauge chambered for 2 9/16 and 2 5/8 respectively.
 
Don’t take it personally. You could make a post about the sky being blue and someone on this website would be up in arms.

Anything that makes your shotgun more useful to you is worth it IMO…..whether it’s a perazzi or an H&R

That’s the way I look at it, do it if it makes you want to shoot it more. I’ve never regreted doing something to a gun that made me use it more or enjoy using it more.
 
What is the down side to having a 3"chamber in a $400 sxs shotgun that came from tradeex? I was under the inpression most all modren shotguns are 3" and it was a pretty standard size 12g shell.

The gun is a Merkel/suhl it was made in November 1970

the down side depends on the taper of the outside of the barrels; the barrels of some guns taper rapidly from the breach forward and that potentially means that you have minimum metal in the forcing cone area

cheers mooncoon
 
A Merkel is a solid and strong shotgun. They were proofed with 2 3/4 inch loads. A steady diet of 3" will take them off face regardless of 3" chamber or not. My Merkel is very light ( made in GDR 1976) 1 1/4 oz. Bismuth is a handful could not imagine shooting 3" loads in it. Recoil would be stout.

Darryl
 
I bought a forcing cone reamer from Brownels in 2012 for $105. Can. $ .
It was 12 ga. & made by Clymer. I used it to reame 2 1/2" chambers to 2 3/4"
chambers. Not for heavier loads , just to use more common hulls which I reloaded.
A couple of times , by accident , I went too far & got a 3" chamber with ease. Still use light loads .
No bores where chrom lined , as this is too hard to reame with my tool .
Always remember ; lengthening the chamber does not mean the gun can handle hotter loads.
 
Thanks for all the info guys.

If i want more recoil which i actually love, id shoot my 500 jeffery chambered P14 or my 8.5 pound 460 weatherby chambered Zastava M70, or my 43 express m98 mauser or 375H&H model 70, maybe even one of my .577bore muzzle loaders with 100gr of 777

My 12 guage isnt it. It lacks the thump. I just want to be able to shoot 2.75 and 3"loads from it so it opens options when aquiring ammo or using the ammo i have on hand. ( all but 8 of my guns are in storage in NS right now, so i only have the one shotgun with me)

2.75 and 3"are both the same 11.5k pressure, yes bolt thrust will be more when moving a bigger payload but having a double bite lock with a greener cross bolt i believe it will stay together with 11.5k psi 3" 1 1/4oz loads.

At the 3" mark on the barrel they are still over 1" diameter, they dont really start to taper until after 3 inches.
 
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I bought a forcing cone reamer from Brownels in 2012 for $105. Can. $ .
It was 12 ga. & made by Clymer. I used it to reame 2 1/2" chambers to 2 3/4"
chambers. Not for heavier loads , just to use more common hulls which I reloaded.
A couple of times , by accident , I went too far & got a 3" chamber with ease. Still use light loads .
No bores where chrom lined , as this is too hard to reame with my tool .
Always remember ; lengthening the chamber does not mean the gun can handle hotter loads.

One often overlooked drawback with this modification is the fact that a future owner 10, 20, 50 years from now could still be blindly stuffing ammunition into that gun that it was never designed or built to use. Fine, you’re using mild loads, but what about future owners, will they? You’ve weakened the gun ( probably not disastrously but surely enough to shorten it’s life) and then you are using more strenuous ammo in this weakened gun. If an accident occurs with this gun sometime in the future that could be traced back to weakening the gun, the ‘gunsmith’ could likely be found legally responsible.
 
Well I guess if the reasons for the lengthening is to be more versatile in the use of 12 gauge loadings and recoil is obviously not an issue you might as well ream it to 3 1/2" that would give you total versatility with all 12 bore loadings and recoil as noted would not be a big deal. You did mention the O.D. of the barrels would be adequate.

Darryl
 
One often overlooked drawback with this modification is the fact that a future owner 10, 20, 50 years from now could still be blindly stuffing ammunition into that gun that it was never designed or built to use. Fine, you’re using mild loads, but what about future owners, will they? You’ve weakened the gun ( probably not disastrously but surely enough to shorten it’s life) and then you are using more strenuous ammo in this weakened gun. If an accident occurs with this gun sometime in the future that could be traced back to weakening the gun, the ‘gunsmith’ could likely be found legally responsible.

Ummm NO, that shotgun was designed to shoot 2 3/4 high base magnums with a wide safety factor, it should handle just about any 3 inch out there.

I've owned a couple of them, back in the day they were considered to be status symbols. There were a few folks that wanted to convert them to centerfire rifle cartridges. I never saw one that was done though.

I never kept any of them, because I'm recoil shy and I've never had a SxS 12 gauge or even a single shot 12 that didn't recoil excessively for my tolerances.
 
I would recommend you shoot 6 rounds of 3" shells through that Merkel just the way it is. Then listen to Ashcroft's wise advice instead of going with the answer you wanted to hear.
 
I would recommend you shoot 6 rounds of 3" shells through that Merkel just the way it is. Then listen to Ashcroft's wise advice instead of going with the answer you wanted to hear.

the answer I wanted to hear was the name of a guy I could I pay to do the work for me. and 6 3" shells would be a actual joke compared to my 10 pound 500 Jeffery or 8.5 pound 460 Weatherby as far as recoil goes.

anyway now have in my hand a forcing cone reamer in hand, thanks to Bearhunter, once its done ill shoot some of my 3" 1 1/8" loads and see if I get scared due to the horrendous recoil or if its just a little blast like firing 3" magnums in my cooey 840 is
 
Yes. But the ammo i have on hand is 3" so i want to be abel to shoot it.

Ill shoot 3" 7/8oz loads


This has nothing to do with shooting heavy or light loads. Its to be able to use 2.5, 2.75 and 3" shells.

Im sorry guys. I didnt realize 3" 12 gauge shells were so controversial. If i was looking for a 3.5" chamber i would expect replies like this. But i though 3" was basically astandard chamber
 
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