doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com When is chambering down the best option?

I have been considering having a spare set of 20ga barrels with pitting at the forcing cone sleeved down to 28ga for use on one of my SXS's. While researching sleeving, I noticed that Kirk Merrington's site also offers rechambering.

From what I am reading, it appears that shorter chamber adapters offer some patterning advantages - allegedly a 28ga fired from a 20ga barrel patterns better than a 28ga fired from a 28ga barrel. I even know people who say the 28ga patterns better than the 20ga.

I do not want the added weight of full length tubes, nor do I want to have to remove a chamber adapter in order to reload. Gauge Mates claims their Gold product can be reloaded without removing the adapter. So...In what scenario would someone rechamber instead of using sug-gauge adapters?

It is kind of like a removable partial verses a fixed permanent bridge with teeth. Removable is moving or loose all the time and chamber adapters go in and out or at best up and down. In teeth they are hard to chew with but better than nothing. Fixed bridges and fixed chamber sleeves both stay in place when they work well you can chew or shoot just like normal. Cost is often the deciding issue. If you can afford chamber sleeves that stay in for ever they will be the most useful.

As to claims that a 28/20 will out perform a 28/28 you may be able to show a on paper difference. But can you use a 2% improvement and really improve your shooting ability? Not likely. These chamber sleeve just give you options and help restore badly pitted guns.

Also if you use fiber wads in a sleeved gun you will get a poor gas seal and blow by of gas with decrease performance. Plastic wads may seal enough but felt wads will not. Some shooting venues are requiring fiber wads instead of plastic wads.

Jon,

Are you using the term "sleeve" to mean a barrel length change, or any type of insert including the chamber length inserts? I have been concerned about the wad sealing properly with chamber inserts, but had assumed that a full length sleeve would eliminate those concerns.

Jawjadawg,
Several different points need to be addressed. First, is your 20 gauge safe to shoot now with the pitted chamber? If its still safe, then it is a cosmetic issue. Second, you should really get a set of Gauge Mate Golds and see how your gun shoots with them in. You will be surprised how well it works. Out to about 30-35 yards it will work very well. If you want to shoot a 28 farther than that you need a full length 28 gauge (bore?) barrel and tight chokes. Third, if you sleeve the barrels,and I ASSUME you are turning the barrels into a mono block and putting on new 28 gauge barrels, will this change how the gun handles? Only an excellent sleeving job, such as by Mr. Merrington, will retain the gun's handling properties. I would put on 30" barrels, but I like long barrels. I have handled re-sleeved guns that were very muzzle heavy compared with the original set of barrels. And finally, is this worth it financially? If money is no object and you are not concerned about resale then have at it. You can also have new 20 gauge chambers sleeved into this gun, retaining the barrels.This would be preferable if it is a high end gun. I shoot some 3/4 oz reloads in my 20s and it kind of makes the 28 gauge not so special. I am a 28 gauge fan, so I still own them as the little red shells are cool. If these are truly spare barrels, I would get them re-barreled to 28 gauge to make a 2 barrel set as long as they will handle well. That would be very cool. Please keep us informed as to how this project progresses.
Regards,
Jeff

If you use a chamber reducer, like little skeeters or chamber mates they work fine. I have seen 12 gauge skeet guns shoot 28 chambers and get very good scores. If your forcing cones are real bad you might consider a custom chamber that covers that problem.
bill

I would not sleeve the barrels due to money. Chamber sleeving should work well for you. A 28 chamber to 20 bore is not a seamless transition. The wad does flex to seal it fairly well. What exactly is your concern? Are your chambers bad or is it just roughness in the forcing cone area? When in doubt ask the expert like Mennington to evaluate your barrels. Sounds like he might be able to clean up the forcing cone area and extend the chamber sleeves to restore area.

What Jon & Bill said. I've posted this image of a 16g Smith victim of chamber lengthening (and likely short magnums) with a bulge at the start of the forcing cone



The barrels otherwise have only minor pitting and good wall thickness. I think 28g adapters that reach past the bulge would be an option. Scroll down to the bottom here
http://www.gaugemate.com/info/sub-gauge-adapters

Briley will sleeve the chamber for $375, but I have heard they will not work on Damascus barrels (but would very much like to be proven wrong)
http://www.brileygunsmithing.com/shotgun_gunsmithing_pricing.html

I have installed 30" Briley 28 gauge tubes in a Baker Batavia Special.

The Baker had a crack in the twist barrel about 6 inches from the
breech end. Now the gun has been returned to service.

I would not have minded 20 gauge tubes, but got these cheaply
on Ebay for about $100.

Mike

Pitting at the forcing cone? Sounds like a non issue to me.

I have an LC Smith double that had a fairly large diameter pit in the forcing cone of one barrel. It was deep enough that I could feel it with a bore gauge, and after consideration, I simply ran a long forcing cone reamer in it without lengthening the chamber. The pit was removed and I have shot the gun a number of years with no problems.