how to glass bed the full foreend of a rifle?

[Whiterabbit]

Here's a good one. Read a good suggestion online. Suggested to empirically determine if your rifle likes full bedding, partial bedding, or full free-floating. Just bed the WHOLE rifle, test. Sand out the barrel taper, test. Sand out the chamber area of barrel (full free-float), test. I think I'd like to try this.

Currently, my rifle is set up like most factory rifles. The barrel is floated from the recoil lug all the way to the tip of the forearm, where there is a light (very light) pressure point on the barrel.

Do you guys recommend I sand out that pressure point to achieve 100% float before bedding? Or can I bed with that very light pressure point in there since the stock will be in 100% contact after bedding anyways?

Thanks!

[Frank46]

I've done a couple mausers and bedded the action and the first cylindrical section of the barrel forward of the receiver. The best one was a swedish mauser that shot really well. Now it shoots even better. The only rifle I've done a full bedding job on was a jungle carbine. The buttstock was so loose it wiggled and the forend wasn't much better. The buttstock went easy. The forend was a real pain as I kept all the military wood and handguard, which meant bedding everything including the handguard ring for the upper handguard. No so called wandering zero with that carbine. Shot very well with S&B factory ammo. What you can do is free float the barrel by removing the pressure point at the tip of the forend first. Shoot it and see if it made any improvement. If you do decide to go ahead sand down the barrel right where the barrel comes out of the receiver. Do is to leave sufficient space for the bedding compound. I usually let everything sit for a couple days so as to allow the compound to set up and cure. If any bedding compound extrudes past the breech end of the barrel I usually use a sanding drum on a dremel tool to remove it. Remember release agent is your best friend as the compound will go just about where it wants. So use plenty. I use johnson's paste wax on the trigger guard screws. And still occasionally have to clean out the threads with a dental pick. Hope this helps. Frank

[leftiye]

As for the complete bedding of the barrel I'd have to ask you why on earth you would want to do that? (wood warps)

I guess I'd say no. Don't remove the pressure point unless you're going to bed about 3 or 4 inches in front of the receiver. Actually, unless you're going to do a good bedding job, I might say to put in pillars and make sure the action/barrel doesn't touch anything else. This isn't a good bedding job either, but loose, not binding on anything anywhere is usually better than flexing and sticking in different positions from shot to shot.

I always bed the rear bolt pad, the receiver area and several inches of barrel on a bolt rifle. FWIW, a mini 14 I had defied the usual pronouncement that they're only plinkers when the stock was sanded to show daylight under the receiver and the ring that grips the gas piston casting at the front of the barrel was removed leaving it loose on top of the stock. It approached 1"groups with a load that wasn't ever tested for accuracy. I shot rabbits with it for years without ever putting it on paper. Sighted it in on rabbits too.

[Whiterabbit]

thanks guys. I am pleased with the results

http://castboolits.gunloads.com/attachment.php?attachmentid=96704&d=1392361844

[fouronesix]

What is the type of rifle? It will be interesting to hear how it shoots.

I've found that usually a fully free floated barrel is more consistent (not always producing the tightest groups but certainly more consistent). I've found that bedding a wood stock the full length in front of the chamber may result in variable accuracy and variable POI (guessing that wood moves as humidity and temperatures change, including the reaction to variable barrel temperatures). Once in a while I've bedded an "up pressure" point (half ring) near the end of the fore stock that has yielded some very tight groups but again it is hard to predict and may change over time.

No way to test it much less prove it, but the full length bedding may also set up an inconsistent and variable node in the barrel harmonics even if the wood remains perfectly stable.

The one exception I can think of off hand that seems to work (mostly) is the old Winchester Model 70 design that has the barrel channel fully inletted along with a forward barrel tension adjustment screw. [Also, a couple of the Winchester M52 models had the two point adjustable barrel support screws- I assume to similarly "tune" the barrel.] While the pre-64 M70 design seems to work pretty well most of the time, it has to change some over time. I don't know if that screw tension sets the harmonics node or acts like a vibration dampener ???

[Whiterabbit]

bolt action? is that what you meant? Hunting. Also hunting.

The goal is first shot accuracy. first shot has to make it where it counts. So if I have to fire one round per day and make adjustments till it is dead on, that's completely fine. So long as I can always count on that on the cold bore first shot. I have talked to rifle builders, and they full-bed their own hunting rifles understanding this caveat. That firing a string of shots may very well result in a loss of accuracy, particularly as the barrel heats up. Also that there's a good chance the barrel will retain heat for longer as a result of full barrel bedding.

There is always a give and take. For this rifle, no expense will be spared to achieve first shot stability, including trying some uncommon yet well known and occasionally used techniques like bull barrel bedding. Even if they contradict known techniques used by some long range competitors. (still other long range bench rest shooters bed their barrels and glue them in there!)

I can always take the bedding right back out. 3-6 hours of sanding should give me .5mm of clearance again.

[fouronesix]

No matter about the type of rifle- as I could see it is a bolt action.

First, cold shot accuracy and predictable POI should be a primary goal for any hunting rifle. If it has a bull barrel then the effects of stock pressure will be lessened. If the bedding compound is of decent thickness and strength then it in itself will help stiffen and stabilize the stock. If the bull barrel is thick enough, most any type bedding- full, partial or free floating may be of little concern. If that's the case then correct action pillar bedding may be more important than the barrel. Just have to shoot it and see.

[Houndog]

For that first shot out accuracy of a cold, CLEAN barrell, DO NOT use any type of oil in the barrell! Buy some lock eeze (a lubricant for padlocks) and use 3 or 4 drops on a patch to finish up after cleaning. Lock eeze is nothing more than colloidal graphite in an alcohol carrier. Your barrell will almost act like a properly fouled barrell. DO NOT just use lock eeze in a firearm you are going to store! It doesn't help with ruct AT ALL!

[leftiye]

Actually, the lube gurus are looking for first shot accuracy in all conditions with barrel at ambient temp, from a fouled barrel with same lube as is on boolits. Not many lubes will do it, but clean barrels will not shoot to same POI as the barrel will shoot after the first shot either. Oil - very light, or graphite as mentioned should be better than clean though. Depending on how good the lube, first shots from a dry barrel can be a disaster. I had a muzzle loader that I lubed the bore after seating the boolit, forget the lube and it hit 10"lower than when lubed.

[felix]

I don't know if that screw tension sets the harmonics node or acts like a vibration dampener ???

Both. ... felix

[felix]

Here's a good one. Read a good suggestion online. Suggested to empirically determine if your rifle likes full bedding, partial bedding, or full free-floating. Just bed the WHOLE rifle, test. Sand out the barrel taper, test. Sand out the chamber area of barrel (full free-float), test. I think I'd like to try this.

As good as any non-proven method for the type of gun on-hand. I remember when Chrysler put together their Viper car from scratch. They got the whole thing put together in nine months from inception using several contractors. But when assembled at the Chrysler plant, the exhaust system designed there sucked BIG time. Sounded "good" to the typical hot-rodders but the system introduced totally unacceptable vibrations throughout the car for dealer sales. Took a year and a half worth of hurried heuristics to pass the marketing specs.