Corking a barrel


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.303
December 22, 2008, 11:05 PM
i have seen many posts that suggest shimming the barrels of enfields, mosins, etc. to improve accuracy. so, two questions

where on the barrel is this done,

and just how effective is it?

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Sinixstar
December 22, 2008, 11:11 PM
There's a thing on box o' truth about this.
Apparently- they had some pretty good results, but had to use a bit of cork.

It's done from what I've seen there, and a few other places - at the muzzle end of the stock.

jpwilly
December 23, 2008, 12:27 AM
Works! Here's the Box of Truth link (http://www.theboxotruth.com/docs/edu63.htm)

Ohio Gun Guy
December 23, 2008, 01:07 AM
Player-Team-Date-Suspension-Offense:
Sammy Sosa-Chicago Cubs-June 3, 2003-Seven games-[2] Corked bat
Wilton Guerrero-Los Angeles Dodgers-June 1, 1997-Eight games-Corked bat
Chris Sabo-Cincinnati Reds-July 30, 1996-Seven games-Rubber balls[3]
Albert Belle-Cleveland Indians-July 15, 1994[3]-Seven games-Corked bat
Billy Hatcher-Houston Astros-September 1, 1987[3]-Ten games-Corked bat
Graig Nettles-New York Yankees-September 7, 1974-No Suspension[3]-Six super balls in bat

Didn't work out very well for these guys! :evil:

rangerruck
December 23, 2008, 01:16 AM
I wouldn't use cork; too bouncy, too reboundy, will absorb water over time.
I would go to Home Despot or someplace, and get the very hard little rubber dome thingys, that you put behind cabinet doors, or the bigger black rubber thingys, that you can put behind full size doors. like this;
http://i13.photobucket.com/albums/a284/pmullineaux/006-4.jpg

I put these under the bbls of ALL My RIFLES!!!!! after I have gotten them as accurate as possible with all my other tweaking jobs, I then use these, to see if they improve the accuracy even more, or not.

paintballdude902
December 23, 2008, 01:18 AM
i read that brits used to use bits of intertube

esmith
December 23, 2008, 01:50 AM
rangerruck, would you mind giving us a link to a better picture, because i have no idea what that is and i would like to. I need to find a better substance than what im using now.

jpwilly
December 23, 2008, 01:51 AM
Bottom line is you are creating a pressure point on the barrel that will change the harmonics and should be the same from shot to shot. This also elevates the bbl above the wood stock so it isn't touching kinda like a poor mans free float. Remington use to use (maybe still does) the pressure point system to make their rifles accurate.

Float Pilot
December 23, 2008, 04:15 AM
A friend of mine has an old hex receivered Mosin that shoots very nice groups. It looks like crap but shoots all day.

Anyway, we were cleaning it up one day and discovered a shim made from folded and oiled newspaper. We unfolded it and found it to be a communist newpaper clipping from Spain.

Our theory is that it was one of the guns the Soviets gave to the anti-Franco troops during the Spanish civil war. Whoever was using it knew how to make it shoot pretty dang good groups.

I have alumimnum shims inside my Isaphore Enfield that I made from cutting up a small cat food can. I moved it to a couple different spots until the formerly horrible accuracy improved to 2-3 inch groups at 100 yards using iron sights.

rangerruck
December 23, 2008, 04:33 AM
that is the best pic I have; what you are looking at is a little pad. it has 4 rounded , clear, hard rubber bumps on it, that are shaped like an Igloo. They peal off the paper backing. you can find these at any home improvement store, or hardware store. these are small , for cabinet doors, and they can very in hardness, and size, up to black soft rubbery ones, to stick on the backs of doors, so they don't slam into walls. go for the smallest hardest ones you can get, as they will be less prone to absorb water, or change shape because of temp changes. stick them on the end of your stock, between the stock and bbl. you will only need one. You may find it interesting, to shoot a group, them move it say 1/4 inch at a time, back towards the receiver, and see if you get a better group or worse group.

Franco2shoot
December 23, 2008, 09:52 AM
It works for 91/30 Mosins, at least here's my experience.

I had read that snipers during the Stalingrad battle improved the accuracy by corking the barrel. Didn't really know what that meant, so I started experimenting with my own 91/30. At first I used the oiled newspaper as was mentioned above. I just placed some up around the first barrel band, and sure enough the first couple shots produced a nice tight pattern. However as the barrel heated up the pattern got wider.

At home while cleaning the rifle in the family room, I glanced into the kitchen and saw my wife pouring a typical Saturday afternoon glass of chardonnay and it struck me. Perhaps these soldaten were using cork from a wine bottle. Hence the term "Corking the barrel".

OK, so off to the cutting board with a modern day serrated blade, and I started slicing the cork length wise instead of the way you would cut salami.
It took several tries but finally, I had three slices that were equal in thickness and looked like rectangles about an inch long and a half inch wide. I ran these across some sand paper smoothed and measured to make sure the 3 pieces were of equal thickness. Next I popped off the barrel bands that hold the top forearm, and I just loosened the bolts that hold the stock and barrel together. Two pieces of cork were slid under the barrel right where the front band goes, with the third over top, so the arrangement equally spaces cork around the barrel. Finally, everything was reassembled, all screws tightened and off to the range the next day.

WOW, the group was reduced to less than an inch at 100 yards, and best of all it has stayed that way for the past 6 months. Groups stay tight whether the barrel is hot or cold. Making me a firm believer.

Hope this helps.

KKKKFL

Bartkowski
December 23, 2008, 07:39 PM
I have done this to a few mosins. I can't say that it has hurt accuracy on any of them. Of course it hasn't helped on any except for one. The one it helped now shoots under 3" at 100 yards pretty easily. The others are still worse than that.

I use a piece of insulation from a flat wire. I needed something very thin, much thinner than most cork comes and I came across the insulation in my trash. I just cut a piece to size, slid it under the barrel right where the stock starts and shot it.

RSVP2RIP
December 23, 2008, 08:19 PM
Try using film negatives. I use these on all my rifle after trying a busines card shim first. Then I measure what ever I first stuck under the barrel (card or several folds of papper etc.) with a micrometer, then match it with film negatives. If it still shoots the same, I'll epoxy the works in if the stock will come off regularly or just leave it. The negatives don't warp, absorb water or shrink with temerature changes. They also work great for shimming scope bases. X-ray film, if you can get it, is great also. You might want to check with your dentist on that one, see if he has any duds lying around.

stubbicatt
December 23, 2008, 09:57 PM
I don't think that rubber inner tube would be such a good idea if the barrel got hot.

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