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Al,

Here's an excerpt from a recent article for Sports Afield, which was primarily about action-screw torque, but also involved other aspects of bedding, including pillars. Thought you might be interested:

"One point of torque involves screw threads, which only take so much torque before they start to deform. When that occurs the screw can loosen during use, resulting in erratic accuracy (or precision—take your pick).

Second, the hardness of the stock can vary, especially wood. The “bottom metal” can also be made of aluminum or steel, and the dimensions actions vary. The tightening method I learned long ago probably originated back when many bolt-actions had relative skinny tangs—the extension on the back-end of the action holding the rear action screw.

Probably the most common skinny-tang action is the 98 Mauser. Multiple millions of 98 actions have been made, and continue to be made, the 98 also became the partial design-base for other actions, such as the 1903 Springfield. The combination of a narrow tang and walnut stock could result in the wood being crushed when the rear action-screw was “over tightened,” also potentially resulting in a loose connection and poor accuracy. This is why many military 98 Mauser stocks included a steel cylinder around the rear action screw.
Many later bolt-actions have very broad tangs, protecting against this tendency, including the Model 70 Winchester, Remington 700 and Ruger 77. The Ruger includes an angled recoil lug, allowing the front action screw to draw it firmly into the stock recess, even if somebody doesn’t hold the rifle muzzle-up while tightening the screw.

Bolt-actions have continued to evolve, with many 21st-century designs lacking the single, front-end recoil lug. Instead they use smaller metal or even synthetic bedding blocks, some designed to fit recesses milled in the bottom of the action. Many also feature “pillars,” metal cylinders epoxied into the stock around the action screws, to help maintain consistent torque and prevent crushing the stock, however slightly.

I also recently consulted three gunsmiths with a reputation for making very accurate rifles—which I know about their accuracy personally, from owning their rifles.

Melvin Forbes, owner of New Ultra Light Arms said he doesn’t bother with torque settings on his rifles, just tightening the screws until they stay firmly in place. He also only fits one pillar in his synthetic stocks, around the front screw to prevent customers from over-tightening and having the screw’s tip end up inside the bottom bolt-lug recess, preventing the bolt from turning. He also pointed out that in stocks with V-shaped bedding blocks to hold round actions, over-torqueing can bend the action slightly.

Mark Bansner, head of Bansner & Company LLC, said he’d recently done some torque tests, finding that with a standard Brownells Mag-Tip screwdriver and either hex- or Torx-head screws, tightening them as hard as possible results in around 60 inch-pounds. He’s not fond of pillar bedding, both because his synthetic stocks are very solid through the action area, and because he’s seen pillar-bedded hunting stocks break at the grip—right where they were drilled-out for the rear pillar.

Charlie Sisk of Sisk Rifles also thinks about 60 inch-pounds works for modern rifles with solid, uncrushable stocks—especially the chassis STAR stock he makes, where the action area is solid aluminum. He pointed out that many if not most hunters either torque action screws way too much, or not enough—the last often due to neglect. Often over-torqueing occurs with individual hex or Torx-head wrenches made of a bent length of steel, because they have long “handles.”

All three gunsmiths mentioned that no matter the specific torque that works for your rifle, you should check the screw-torque periodically. They’ve all had customers bring in rifles that had “quit shooting.” Tightening the action screws fixed the problem.

John

Since you say your rifle is a Ruger M77 Mark II, here's a little trick I found that worked for me. I had an All-Weather Hawkeye in 338 Federal. It shot just OK at first but I read on here somewhere that if your mag box is binding you should file it down a bit in the notches until it wiggles a little when re-assembled. My groups went from 1 1/2" down to about 3/4" after I did that. I used a Dremel tool with the round "barrel" sander. It fit the notch just about right. A small flat file would work too. I remember reading that if you open the mag floor plate & put your fingers inside and try to wiggle it, it shouldn't bind. Go easy on it. Re-assemble and keep trying until it wiggles a little. Apparently it torques the action or something if it's too tight. Good luck.

Thanks for posting that, John... nicely written.

On the really light weight stocks, I like to inlet a reinforcement that angles through the wrist and is bonded to the rear pillar. Aluminum round stock or round carbon fiber rod work well. The upper end is profiled to match the pillar and bonded to the pillar.

Good shootin' -Al

I used to do something similar when I was using timber stocks, before bedding the tang I would drill and insert a 4 inch wood screw angled down thru the pistol grip and dress the head so it was just below the bedding surface
This strengthens the stock in its most vulnerable area and then I would bed the action front and rear in devcon epoxy steel using a thin walled front pillar that was glued in to contact the front of the floor plate and not quite touch the action
Edited to add that the reason fo using a thin walled pillar is that these were slim hunting rifles and I didn’t want to remove too much timber

Glad you got it worked out. If that was my rifle I'd also bed the action. I use Devcon 10110.
But some rifles are horrible shooters. I bought a used custom Win Model 70 in 270 WSM that was a real dog. That rifle wouldn't shoot better than 2 MOA with anything or any work. Thank goodness I picked it up for a song (that's probably the reason) and sold it online to Guns.com for 3x more than I paid for it. It was worth all the frustration.

One note about both the Bansner and, especially, NULA stocks:

They're already both very strong through the grip area--especially the NULAs, due to Melvin's use of lengthwise graphite fibers, and epoxies developed by the aerospace industry. (One of his friends--and original investors--is an actual rocket scientist, for Hercules. Or was before he retired. I know this mostly through meeting the guy, who I've fished and hunted with. We occasionally talk--though mostly about fishing and hunting. But he called a few weeks ago to make sure he was on the list for the new book...)

Anyway, a few of Melvin's many customers have had horses roll on his rifles during hunts. So far none of the stocks has broken broken, even though the barrels have sometimes bent!

When I bought my latest Bansner stock Mark said it did not need pillars as long as I don't "gorilla crush" the screws. So I didn't install pillars.

Yeah, Mark's not a big pillar fan!

Have used his stocks for over 25 years now, and never installed pillars. All were on big game rifles, which shot very well, as in 3-shot groups in around half an inch--including the FN Mauser .338 Winchester Magnum that weighed around 7-1/2 pounds with scope.