Discovered my howa action screws had loosened up

[grayfox]

In process of changing out my trigger springs to a 2-2.5# set, I noted my Howa action screws had loosened up on me, with my pro varmint stock. I had torqued them -- what, last year? and hadn't had anything apart since then.... maybe that explains some of the more erratic shot groups lately for known good-accurate loads.
Note to self: don't think it won't happen to me...!

Anyway, I swapped out the springs and now have a 2.5-2.75# (my analog pull gauge) pull which is definitely better than the original. Plus I re-torqued the action screws on re-assembly.

Question: has anyone tried a silicone o-ring or similar to better hold torque, or just use some (blue- I guess) loktite?

My loads are doing well again (see uploaded pic) but I'm hesitant to take it out on a hunt until I better lock down the action screws.

3 shots target (center right) from the bench, 100 yds, 0.405" ctc. (note, the center and lower left were Creedmoor, 3 shots each, different day).



Deer target, shots to center mass, and 1 to the heart, 100 yds (field position, fwd-tripod and unsupported rear stock)

65Grr-Howa-110CCh121618.jpg

[Dinny]

Is the stock bedded? Aluminum pillars might solve your problem and help with consistency.

Thanks, Dinny

[grayfox]

Not bedded. I had a GS work it over when seating the bottom met.... ah, plastic, I don't have a drill press so not sure I could drill out for the pillars... I've got the DIPinc metal now but funds are a bit low for having GS do the bedding.


eta: how much wider do you drill to insert those pillars?

[A5BLASTER]

Not bedded. I had a GS work it over when seating the bottom met.... ah, plastic, I don't have a drill press so not sure I could drill out for the pillars... I've got the DIPinc metal now but funds are a bit low for having GS do the bedding.


eta: how much wider do you drill to insert those pillars?

Score high piller kit says to use a 9/16 bit to drill the action screw holes out with for the pillers.

I like high strength red locktite on any kind of screw or bolt that needs more then 25 inch pounds of torque.

Mine are set too 35 on the front and 40 on the rear screw.

[Frontier Gear]

I’d recommend the blue Locktite along with pillar bedding.

[FW Conch]

As Denny suggested, You really need pillars in the long run, to insure consistency and because even laminate will crush over time. Although maybe not so much with plastic bottom. I don't know if Your bottom plastic has metal inserts like Savages do ? There's no substitute for metal to metal contact from bottom to action.

However, You can get acceptable performance and decent hunting accuracy from Your current set up, as I have done with some of My builds.

You could try putting a drop of Blue Locktite on Your action screws and let it dry before installation, like some hardware packages come these days. And check the torque on a regular basis.

But no matter our level of shooting, We all want maximum accuracy, and bolt actions help with that. At some point it's pillar and bed and "loose the plastic".

But We need to keep in mind, its the plastic that holds cost down, and We can always pay more in metal upgrades.

Edit: another thought, if Your recoil lug is floating in mid air, it allows the entire system to move with recoil, and definitely needs to be bedded.

[grayfox]

I've used blue locktite before, but never let it dry first... this is doable. I've got the metal DIP bottom metal, so no plastic down there.
I've been thinking on whether to try putting in pillars but not do the epoxy bedding. Drilling the 9/16 straight will be the challenge.
I'll have to look at the recoil lug, I think the GS fixed it "a bit" (confess I forget what that means) but I could do some bedding behind it.
Trying to stay within my skill set.
This thing definitely shoots well when I can get a nice steady stock rest, probably better than I do right now!!

Appreciate all the suggestions!

[Frontier Gear]

Locktite doesn't "dry". It hardens with the lack of air. That is why it gets hard once it is sealed between the threads. This is also why the bottles are always shipped half empty. If you fill a Locktite bottle full, it will turn into a solid chuck of plastic.

To pillar bed your rifle with a hand drill:

Put it in a vise with either soft jaws or with an old cloth such as a towel for padding. Drill only half way through the hole. Watch the drill bit from the side (not the top of the drill) to make sure you are staying straight up and down. You can have a friend "spot" you from 90 degrees to make sure your bit is straight up and down in that direction as well.

Flip the stock over in the vise and finish drilling through from the other direction in the same manner.

You can drill the hole a little bigger then the pillar as the epoxy will fill in the gaps. Just make sure that the action and barrel are centered when the epoxy is curing.

[bj139]

I have a OEM Hogue stock for a Howa 308 and it has aluminum pillars factory installed. Sometimes an upgrade may not be an upgrade.
I will check my OEM Grendel Howa stock.

Edit: I just removed my OEM Howa mini stock from my Grendel and guess what? Aluminum pillars....hm, upgrade?

[Frontier Gear]

I have a OEM Hogue stock for a Howa 308 and it has aluminum pillars factory installed. Sometimes an upgrade may not be an upgrade.
I will check my OEM Grendel Howa stock.

Edit: I just removed my OEM Howa mini stock from my Grendel and guess what? Aluminum pillars....hm, upgrade?

Yep the factory LSI stock on the Grendel is pillar bedded. It has two flaws though, and one of them is pretty major.

The first is that the inletting at the rear pillar is wrong under the bottom metal. It is cast at the wrong angle. Remove the front action screw and then tighten the rear action screw, then watch what happens. The bottom metal sticks way up out of the stock at the front action screw. You can fix this with a little epoxy bedding under the bottom metal at the rear action screw. The DIPinc bottom metal masks or hides this flaw though as it is stiff enough to support the rear action screw on it's own. The factory plastic bottom would split at this location.

The second flaw is that the fore end of the stock has a fair amount of flex to it. Mine wouldn't hold a group at all if shot off of a bi-pod, while I could get 1MOA if it was supported under the front action screw.

Those were the two main things that drove me to getting a stiffer wooden stock and doing my own bedding.

[bj139]

Yep the factory LSI stock on the Grendel is pillar bedded. It has two flaws though, and one of them is pretty major.

The first is that the inletting at the rear pillar is wrong under the bottom metal. It is cast at the wrong angle. Remove the front action screw and then tighten the rear action screw, then watch what happens. The bottom metal sticks way up out of the stock at the front action screw. You can fix this with a little epoxy bedding under the bottom metal at the rear action screw. The DIPinc bottom metal masks or hides this flaw though as it is stiff enough to support the rear action screw on it's own. The factory plastic bottom would split at this location.

The second flaw is that the fore end of the stock has a fair amount of flex to it. Mine wouldn't hold a group at all if shot off of a bi-pod, while I could get 1MOA if it was supported under the front action screw.

Those were the two main things that drove me to getting a stiffer wooden stock and doing my own bedding.

My factory bottom plastic has not split yet. I torque the action screws about as tight as I can comfortably turn with a screwdriver.
I don't crank it as if I am an 800 lb gorilla. They hit a pretty hard stop. Any more would crack plastic.
I can flex the forend but just the weight of the lightweight barrel does not make the forend hit the barrel in a horizontal position.
I like the feel of the rubber coated stock and it is quieter in the woods.

[HokeyPokeyKid]

Unless you pillar bed the stock it will slowly compress over time needing constant re-tightening of the action screws. This effect is especially bad with soft, molded plastic stocks.

[bj139]

Not bedded. I had a GS work it over when seating the bottom met.... ah, plastic, I don't have a drill press so not sure I could drill out for the pillars... I've got the DIPinc metal now but funds are a bit low for having GS do the bedding.


eta: how much wider do you drill to insert those pillars?

The center spur of these spade bits will keep it centered on a smaller hole. Drill halfway from each end. This works pretty well.
If you are a little off at the middle, the epoxy needs some space to fill into anyway.

https://www.lowes.com/pd/IRWIN-Pro-Assorted-Woodboring-Spade-Drill-Bit-Set/1000679371

[Frontier Gear]

My factory bottom plastic has not split yet. I torque the action screws about as tight as I can comfortably turn with a screwdriver.
I don't crank it as if I am an 800 lb gorilla. They hit a pretty hard stop. Any more would crack plastic.
I can flex the forend but just the weight of the lightweight barrel does not make the forend hit the barrel in a horizontal position.
I like the feel of the rubber coated stock and it is quieter in the woods.

I kind of liked the factory stock as well. Once I added a cheek riser, it wasn't bad for hunting and I didn't mind getting it scuffed or scratched. If I was to keep the LSI stock and the bottom plastic, I would probably bed a little epoxy under the bottom plastic at the rear action screw, just to minimize the flex of the trigger guard.

[bj139]

I kind of liked the factory stock as well. Once I added a cheek riser, it wasn't bad for hunting and I didn't mind getting it scuffed or scratched. If I was to keep the LSI stock and the bottom plastic, I would probably bed a little epoxy under the bottom plastic at the rear action screw, just to minimize the flex of the trigger guard.

I will look into that the next time I feel ambitious. I should get the bottom metal but I was waiting for my bottom plastic to crack first.