Howa Mini: Pillar Bedding?

[ntsqd]

Howa Mini Lightweight going into a Boyd's laminated stock. Plan to pillar bed it because I can. Am using Devcon Aluminum Putty because I'm well familiar with it in other uses. I've only bedded 3 rifles thus far, & two of those were rimfires.

The placement of the forward action bolt hole in the bottom of the recoil lug leaves me with a question. Zero the top of the front pillar on the bottom of the lug, or zero it on the bottom of the action? I'm used to leaving a small (1 electrical tape thickness) gap at the bottom of the recoil lug, so this is not a situation that I've found discussed. I've got to think that it has been, I just didn't find it.

As an aside, these action bolts are M6 X 1.0 Torx Button Heads. Titaniumbolts.com or something like that was able to supply Ti Torx Button Heads in the correct lengths. This build's goal is under 5 lbs., designed to be a CA A-Zone (aka "hiking uphill with a rifle") hunting rig. Even with a Leupold Lightweight 2-7x & Talley one piece mounts it's probably not going to make it, but gotta have high goals to achieve high results, right?

 

[KRP]

If you zero the front pillar to the action it won't sit into the stock correctly, the front will be jacked up 5/16"(or whatever the recoil lug to action depth is, I didn't actually measure one). I'd just set the pillar a little short and bed over it like I normally do. If you want pillar to action contact you'll need to use the lug as the reference point, it is part of the action and will set the depth in the stock.

 

[ntsqd]

Thinking on this further, I think my concern is that if I zero on the bottom of the lug, and then bed the bottom of the action that in atmospheric conditions different than the day that I did the work that those two surfaces will not be in exactly the same place and will be influencing the action. If I zero to the bottom of the action then there should be a gap between the pillar and the bottom of the lug. I would mill a step in the end of the pillar to achieve this. Then action bolt install torque will become crucial to accuracy. Which in my mind, and I probably have this wrong, but the whole reason to pillar bed is to reduce or eliminate the install torque's influence.

I'm probably over-thinking this. In rapid fire the POI of the first two rounds are close, but by the third round the feather-weight profile barrel has moved the POI anyway. I know that from shooting it free-floated (Boyd's supplies the stock this way) but un-bedded.

EDIT: I should add that I'm not buying anyone's ready-made pillars. Too easy to make them on the lathe. Then I can make them exactly the right length. I do put a couple partial depth cut-off tool grooves in them for mechanical key with the epoxy.

 

[KRP]

I'm probably over-thinking this.

I think you are...the recoil lug is integral to the action.

What are you doing for bottom metal? The factory plastic piece won't allow you consistent torque on the action screws. I wish Howa would offer this action with the same style floorplate and mag box as there other rifles. The fact they machined the action specifically for a DBM(no feed rails in the action) has me thinking about how to convert one.

 

[ntsqd]

It still is two separate surfaces at different elevations, bottom of the action vs. bottom of the recoil lug. Were this a 1000 yard bench machine it probably wouldn't be acceptable for both surfaces to be bearing. I can see why it would be designed this way, but its too bad that they did. In this case the interference is probably minimal compared to the other accuracy degrading 'features'.

I have dip bottom metal, but frankly I've pondered shortening a mag and bonding it into the OEM piece. Mostly to smooth the bottom of the rifle and reduce snagging points, but partly to eliminate the too easily triggered mag catch from being able to drop the mag somewhere a ~1/4 mile back. With the dip part in place and using the Ti action bolts it weighed 0.1 lbs more than with the plastic part and the steel bolts. I think the weight is worth it, but it just makes the 5 lb. goal that much harder to achieve.

I'm sort of OK with the DBM concept so long as they're not hangy-down parts (like this is). They should be flush to the bottom of the stock or nearly so. I don't need nor want a "tacticool" hunting rifle and needing 10+ rounds in a game rifle tells me the owner's not a marksman.
I've wondered what the polymer used for the bottom piece (can't call it "bottom metal") is? Really hoping its not nylon as that will change the tensile loading of the action bolts with changes in humidity.