When bedding Remington 700's (722, 721, etc), it was long considered proper to provide cearance along the sides of the receiver so that the only points of contact were at the receiver ring, behind the recoil lug, and under the tang. This was usually accomplished with a couple layers of masking tape. The thinking was, since the stock would deflect along the sides under recoil forces, there was a chance of minute stress points when it didn't return to the same place (keep in mind, this was within the context of precision rifle building) and zero contact was consistent. This system still works very well but, as has been amply demonstrated in the intervening fifty years, it probably is not critical and full bedding of the action works every bit as well and looks better for the customer. I have, over the years, bedded rifles both ways and lost matches to rifles bedded either way!
When bedding Model 70's, many did things the same way but did bed under the center screw as well; to the extent that they could, anyway. There is not a lot of surface there. Others chose to eschew contact at the center screw location and bedded at only the receiver ring and tang. Clearance was provided at the bottom of the recoil lug although the sides and front of the lug were, and are, frequently bedded according to the whim of the one doing the bedding. There seems to be little difference in performance and I like to clear the front, sides and bottom just to make stock removal and replacement easier.
I like to incorporate the center screw as part of the bedding system rather than just a support for the trigger guard and will do so by using a pillar at that location. As it happens, I have a Winchester Model 70 which has three different stocks, all of which are bedded differently so I can make a pretty good direct comparison. The Rifle is a short action, push-feed Model 70 which has been bored and re-threaded at the receiver ring to 1 1/16"x 16 TPI. I retro-fitted bumps at the rear of the bolt to close up tolerance and provide better alignment. It has been fitted with numerous barrels but, for the comparison, I used a particularily good shooting 308 barrel. This is a 23" barrel, gain twist (15-13.5) and contoured to .750 at the muzzle.
The stocks are:
1. A walnut, modified-factory stock which has been fitted with an aluminum bedding block with the 2- round magazine integral to the block. The fore arm is flat and 2 1/4 inches wide and the butt is shaped to ride the bags better. I cobbled this together for a one-time foray into Hunter Class BR. It is skim bedded with Acraglas over the block and uses all three screws. Shooting 150 Sierras it would group five shots at 3/8 or better and was capable of shooting 50's with a good x-count.
2. A laminated, Marksman style, prone stock which is pillar bedded at all three screw locations and is bedded all along the sides. In this stock, using the same barrel, it will group five into 3/8 and I can usually stay under 1 moa prone, with a sling, for five shots.
3. The third stock is a glass/carbon fiber silohuette stock from Steve Wooster from Washington state. This one is bedded at the receiver ring and tang only (no middle screw) and, off the bench, will shoot groups just about the same for five shots with the same barrel. With the barrel I use for MS shooting (a 26" Krieger, 13 twist), it isn't quite as good but still shoots about 3/4 moa. Sadly, my inability to hit my own butt, with both hands, prevents me from doing what the rifle will, offhand.
All this shows is that various bedding systems, assuming similar quality, will produce similar results if all else is equal. In other words, the real measure of a bedding job is on the target.
My best shooting Model 70 prone rifle uses a bedding block, has a solid bottom and is bedded ahead of the trigger group only; the tang floats. The second best one is bedded for the whole action and has a magazine and I suspect the real difference between them is that one has a better barrel. GD
