This is topic Clearance in forum Firearms forum at The New Huntmastersbbs!.
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Posted by albert (Member # 98) on March 11, 2004, 12:54 PM:
When full floating a barrel what kind of clearance does one need? how do you check this?
Thanks again
Posted by Leonard (Member # 2) on March 11, 2004, 05:01 PM:
Any clearance is enough clearance. Mostly. Depends on what the stock is made of, and if it is wood, which can warp.
However, if it is sufficently sealed along the barrel channel, warpage is not usually a problem, except for Alaskans, etc.
If the barrel is subject to overheating and thereby touching the fore stock, (although not a consideration in most hunting situations), then you need more clearance.
A lot of people, dealing with fiberglass stocks, want to see enough clearance to slip a business card between the stock and the barrel along the entire length. Not a bad idea.
If you are dealing with a pencil barrel, you might want to install a bridge for a little forearm pressure, but that is something you can try later, if freefloating isn't satisfactory.
Good hunting. LB
edited for spelling
[ March 11, 2004, 05:03 PM: Message edited by: Leonard ]
Posted by Jack Roberts (Member # 13) on March 11, 2004, 10:36 PM:
When you fire a round the barrel whips a lot more than most people realize. Slow motion pictures make it look like a rope somebody whipped. Stock flex is also a factor. Most stocks are quite flimsy. The laminated stocks and high end composites, like McMillan, are very rigid. But they are the exception not the normal.
With a heavy barrel and pretty stiff stock, I want a minimum of .040", which is about 2 business cards. With a thin barrel and a flimsy stock, 1/8" may not be enough.
A quick test is to smack the forearm smartly with your palm and see if you can make it contact the barrel. If you can, you do not have enough clearance. And if you can smack the barrel and make it contact the stock, you do not have enough clearance.
There is no penalty for too much clearance. Many match rifles now just cut the stock off flat 1/4" below the barrel. My favorite, because it also helps cooling the barrel.
Jack
Posted by varmint101 (Member # 41) on March 12, 2004, 05:54 PM:
So, say you have a rifle that shoots ok but not great. And you think free floating the barrel is the ticket. Do you just take it off and sand it down or dremel it or do you need sealant and other stuff?
Matt
Posted by Leonard (Member # 2) on March 12, 2004, 07:14 PM:
Yeah, it can be involved, coating the barrel with a light grease, and seeing what transfers, or just hog it out. But, I'd bed the action before free floating, or better yet, do both at the same time.
Almost guaranteed that it won't hurt, and would most likely help accuracy.
Good hunting. LB
Posted by Az-Hunter (Member # 17) on March 12, 2004, 08:21 PM:
I can't remember, but maybe one rifle, that didn't shoot better after free floating the barrel and bedding the action. I don't get quite as enthusiastic as Jack in my hogging of the barrel channel, but an easy slip of a business card between my barrels and wood, and I call that good. I use a series of two wooden dowels, of varying circumference, wrapped with coarse then medium sand paper as my channel rasp....crude, but works reasonably well. An application of sealer on the raw wood in channel, and your good to go. The bedding is a procedure some guys shy away from, but it's not all that difficult to do. Anyone who has done this job can tell you......when you think you've used enough release agent on metal that will be contacting the bedding compound, use some more, be very liberal with it. They usually provide it with the bedding kit, but there are numerous "secret compounds" guys like to use. Ive used Johnsons paste wax more than one time with good success. Along this same topic, have any of you guys ever had a rifle that shot "better" with that damned forend pressure pad in? Every rilfe Ive got into that had one, seemed to breath new life after removing the pad and free floating.
Posted by Jack Roberts (Member # 13) on March 12, 2004, 10:56 PM:
The Olympic and World Cup shooters don't take any chances. Just cut the stock horizontally 1/4" below the barrel.
If you want the 1940s custom stock look, try for the minimum clearance.
Your choice, go for it!
Jack
Posted by Rich Higgins (Member # 3) on March 13, 2004, 08:16 AM:
I agree with Jack. If you are a fan of the Olympic and World Cup look, simply take a chainsaw longitudinally through the center of your stock and eliminate the pressure problems due to barrel whip in one fell swoop.
If you are a fan of the 1940's artist's appreciation of the warmth and beauty of well figured hardwood and appreciate the artistry and technical precision an artisan can impart to the joining of metal and wood, then you can do as Leonard and Vic describe. Enlarge the bottom and lower sides of the barrel channel with a Dremel tool and arbor bands (hawg it out), then spray the channel with disclosing wax, snug the barreled action into the stock and fire a round. Spot reduce the pressure points along the sides revealed in the wax with sandpaper wrapped around a dowel of proper size and repeat until contact is no longer made after firing five rounds in succession. That usually does the job. Often you can keep tolerances so close that you can barely slide a dollar bill the length of the barrel.
Posted by Leonard (Member # 2) on March 13, 2004, 08:37 AM:
Yeah, the beauty of it is that either method will likely get you "minute of coyote" accuracy.
It's amazing how far we have "progressed" in the quest for accuracy, space age composites, etc. But some of those 1940 rigs are still shooters, while the high tech jobs seem to last, (what) 1500 rounds?
Good hunting. LB
Posted by Barndog (Member # 255) on March 13, 2004, 11:22 AM:
MOC (minute of coyote) is this a new term? I like it, does it account for the variablity of a moving target in windy conditions?
Posted by varmint101 (Member # 41) on March 13, 2004, 10:22 PM:
lol Minute of coyote I already have. Minute of fly would be cool though!! Thanks for the replies. I find it all fascinating.
Hey, anyone live around Phoenix? I'm going to be in Scottsdale and Tempe the 19-22 of March for the SilverCrown and IRL race. Wondering if there's anything to do besides baseball games? (which I will be doing that too)
Matt
Posted by Jack Roberts (Member # 13) on March 14, 2004, 06:29 PM:
varmint101
Dehydrating is quite popular.
Jack
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