Reaming a Shotgun Bore

[Bomberman]

I have a 12 gauge over/under that I love to hunt with but it is bored for 2 /34 inch shells. I also love to hunt waterfowl and want to use 3 inch shells to get the maximum pellet count for cleaner kills. I would like to have my shotgun reamed out to be able to accept 3 inch shells.

Has anyone had any experience doing this kind of work themselves? I'm interested in hearing any problems encountered, tips, advice, etc. Also any alternatives to buying a reamer for $150+ for a one time use.

Thanks in advance for any input.

[Bodean98]

Bomberman,
Read the write up "You can do it" in the barrel works sub section of this forum. Good "how to" on the subject.

[bubba.50]

don't recall the name right off but, there are a couple places that rent reamers.

[bubba.50]

4D Reamer Rentals LTD shows a 3in finish reamer for $33.00 and gauge(I guess like a go/no-go gauge) for $4.00 a pretty hefty deposit is required.

[pietro]

.

Since you didn't post what O/U you're considering reaming out for 3" shells, IMO you would need to first do some homework, as not all shotgun bores/chambers are created equal................... and you could be into a "catch-22" situation.

If your O/U's bores are chrome-plated (which is a plus when hunting waterfowl, using the required steel shot), the plating would first need to be removed before reaming (AFAIK plating would damage a reamer).


If your O/U's bores are not chrome-plated, the required steel shot will permanently score the bores. ( a work-around would be the use of Bismuth, or some other non-lead shot).


Another thing to consider is that, if your O/U is a lightweight, the use of 3" magnum shotshells can be punishing (to both gun & shooter).

[Cap'n Morgan]

I reamed a few chambers from 2-3/4" to 3" Nowadays I shoot 3" in my 2-3/4" guns and don't worry about it. Early shotguns had very abrupt forcing cones, some of the earliest none at all, and a too long case could spell trouble. In my personally opinion it's totally safe in modern shotguns with their rather long (1/2" to 1-1/2" or longer) forcing cones. Back in the seventies and eighties many shotshells came in 67.5mm length for use in old 65mm (2-1/2") chambers.

This is not a recommendation to shoot the wrong size ammo in your shotgun. Like I said; just a personal opinion...

[KCSO]

#1 Measure the barrel walls!!! You can't remove too much from the forcing cone area it might bulge. #2 You need a reamer and if the barrel is chrome bored you need hones to remove ALL traces of chrome before you ream. #3 If it measures out you ream and then polish with a felt bob and grits of polish till it's smooth and shiny usually 400 is enough with a hard felt bob.

Or mail it to me and if it measures up it will run you $30 a tube.

[Bomberman]

Bomberman,
Read the write up "You can do it" in the barrel works sub section of this forum. Good "how to" on the subject.

Thanks for pointing that out to me...answered a lot of questions. Great how-to article.

[BwBrown]

I have a fair hobby shop - couple Bridgeport mills, couple lathes...
I toyed with trying this myself with rented reamers. Then I called Mike Orlen. Not only did he save me making a serious rookie mistake (due to not having adequate ID measuring tools) but he did the work for me, at reasonable cost and in less than a week turnaround time!

Michael R Orlen
79 Salem Street
Amherst, MA 01002
(413) 256-1630

[Ballistics in Scotland]

#1 Measure the barrel walls!!! You can't remove too much from the forcing cone area it might bulge. #2 You need a reamer and if the barrel is chrome bored you need hones to remove ALL traces of chrome before you ream. #3 If it measures out you ream and then polish with a felt bob and grits of polish till it's smooth and shiny usually 400 is enough with a hard felt bob.

Or mail it to me and if it measures up it will run you $30 a tube.

I think there is very little chance that a modern barrel in good condition will be bulged by reaming a 2¾in. chamber to 3in., or that the action wouldn't be strong enough. Recoil might be undesirable, though. The old standard that the shot shouldn't be over a hundredth of the shotgun weight still holds good. The 3½in. chamber is the one to beware of, though.

If a shotgun is going to burst from overpressure alone (rather than an obstruction or a faulty barrel or receiver), it will almost certainly begin where the front of the chamber makes the wall thinner than either behind or immediately in front of it. Even with a long forcing cone you do not want to push that chamber ½in. or ¾in. along the taper of the barrel.

Incidentally you don't need a headspace gauge for a shotgun already correctly headspaced. The 2¾in. and 3in. cartridges have the same rim and rim recess, and you won't take any harm from stopping at a 2.99in. chamber in order to be sure of not cutting the rim recess too deep.

[Blackwater]

Nobody's mentioned the main problem here yet. You didn't say what wt. your gun is. A buddy once had a Win. 101 with 3" chambers and Win Chokes. He brought it over to pattern it with some 2 oz. 3" mag. turkey #5's. We set it up and he shot one round at the target we'd set up. His was the lwt. "bird gun" version and didn't have a recooil pad. The full barrel shot 75% after we got through marking with magic markers and counting up the results. He was clearly a little disappointed, so I kept bugging him to try the mod. choke lower barrel. He steadfastly refused, and a few days later showed me the bruise on his shoulder. But that day, I kept bugging him and telling him how large pellets tend to require less choke to get tight patterns, and he finally shoved his gun at me and said, "Well HERE! YOU shoot it!" A sudden realization poured over me that that such a light gun just MIGHT hurt if you shoot those heavy loads in it. But as the old saying goes, "In for a penny, in for a pound," so I rather soberly took it and the shell he offered me, and did my due penance, and shot it. As it turned out, it actually shot a 96% pattern! And yes, that day he showed me his bruise, I had a like one to show HIM as well! We went in and had a little drink and a laugh about it, but that didn't keep it from hurting for about a week!

So though some things CAN be done, whether it's WISE or not is sometimes a whole 'nother question. Hopefully, you're tougher than we were that day, or your gun's heavier and has a good pad on it. If so, you're in business. If not, it's probably best to just get a dedicated gun for heavy loads like the 2 oz. 3" shells. Only took one shot for me to learn this. I also have a friend who's shot literal elephant rifles, and got fine accuracy off the bench. One shot from one of the 3 1/2" Mossberg pumps with the short barrel, though, and he won't shoot another one. Those things come back HARD, and the stock design isn't all that great for recoil, either.

Just another aspect of these conversions that I sometimes see left out of the mix of opinions and advice.

[Duckiller]

You don't need chrome lined barrels to shoot steel!

[Menner]

Steel shot does not scar your barrel it travels down the barrel inside a plastic wad or shot cup. the only thing about steel shot that will hurt your barrel is if you shoot it through a restrictive choke (true full choke) because steel will not compress as it passes through the choke it can and will warp a barrel.
the steel shot myth has been around since the 70's (just like you can't shoot them lead bullets without getting lead in your barrel) I have shot thousands of steel shells through my Rem 1100 the barrel is an original 3"mag full choke barrel that I had cut and tubes put in. no scaring
Tony