Action Screws - 30/40 in lbs too light?

Full Curl

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May 4, 2012
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Last weekend I was at the range with my 300PRC throwing pills out to 600yds. My POI seemed to move a little higher vertically. First thing I did was check my action screws and yep, the front was loose. I just had the rifle built 2 years ago and never have had to tighten either action screw before. I contacted the reputable builder and was told 65 inch/pounds for the front screw. I torqued it down to 65, checked that the rear screw was tight and went back to the range. I was all over the place, I had 4-6 inch groups at 100yds. This is normally a ½ MOA or better rifle. After checking over everything else, I went back to the front action screw and loosened it just to see if things changed. I didn't have a torque wrench with me at the range but I tightened it up pretty snug which was less than the 65 inch pounds. Rifle went right back to zero, grouped great, and dialed spot on. I checked the torque on both action screws when I got home and the front is at 40 inch pounds and the rear is at 30 inch pounds. They are both tight but not cranked. This seems light to me but the rifle shoots great. I fired another 20 rounds and they never loosened at all. I wanted to get some feedback from you guys, is this too light, should I be at all concerned?? This is a carry/pack-in hunting rifle so it sees some boot miles. I plan on just putting a couple witness marks on the screw heads and holes and hunting with it. Correct or not, 65 inch pounds sure seems like a lot of pressure on things to me. Thoughts?

Rem 700 clone BDL bottom metal pillar bedded into a McMillian A3.
 
I wonder if 65"lbs is putting the front pillar hard against the action (metal to metal), while ~40"lbs provides pillar clearance.
I see the term 'pillar bedded' as a misnomer, given that pillars are not bedding.
 
Last weekend I was at the range with my 300PRC throwing pills out to 600yds. My POI seemed to move a little higher vertically. First thing I did was check my action screws and yep, the front was loose. I just had the rifle built 2 years ago and never have had to tighten either action screw before. I contacted the reputable builder and was told 65 inch/pounds for the front screw. I torqued it down to 65, checked that the rear screw was tight and went back to the range. I was all over the place, I had 4-6 inch groups at 100yds. This is normally a ½ MOA or better rifle. After checking over everything else, I went back to the front action screw and loosened it just to see if things changed. I didn't have a torque wrench with me at the range but I tightened it up pretty snug which was less than the 65 inch pounds. Rifle went right back to zero, grouped great, and dialed spot on. I checked the torque on both action screws when I got home and the front is at 40 inch pounds and the rear is at 30 inch pounds. They are both tight but not cranked. This seems light to me but the rifle shoots great. I fired another 20 rounds and they never loosened at all. I wanted to get some feedback from you guys, is this too light, should I be at all concerned?? This is a carry/pack-in hunting rifle so it sees some boot miles. I plan on just putting a couple witness marks on the screw heads and holes and hunting with it. Correct or not, 65 inch pounds sure seems like a lot of pressure on things to me. Thoughts?

Rem 700 clone BDL bottom metal pillar bedded into a McMillian A3.
IMG_0038.png
 
Last weekend I was at the range with my 300PRC throwing pills out to 600yds. My POI seemed to move a little higher vertically. First thing I did was check my action screws and yep, the front was loose. I just had the rifle built 2 years ago and never have had to tighten either action screw before. I contacted the reputable builder and was told 65 inch/pounds for the front screw. I torqued it down to 65, checked that the rear screw was tight and went back to the range. I was all over the place, I had 4-6 inch groups at 100yds. This is normally a ½ MOA or better rifle. After checking over everything else, I went back to the front action screw and loosened it just to see if things changed. I didn't have a torque wrench with me at the range but I tightened it up pretty snug which was less than the 65 inch pounds. Rifle went right back to zero, grouped great, and dialed spot on. I checked the torque on both action screws when I got home and the front is at 40 inch pounds and the rear is at 30 inch pounds. They are both tight but not cranked. This seems light to me but the rifle shoots great. I fired another 20 rounds and they never loosened at all. I wanted to get some feedback from you guys, is this too light, should I be at all concerned?? This is a carry/pack-in hunting rifle so it sees some boot miles. I plan on just putting a couple witness marks on the screw heads and holes and hunting with it. Correct or not, 65 inch pounds sure seems like a lot of pressure on things to me. Thoughts?

Rem 700 clone BDL bottom metal pillar bedded into a McMillian A3.
 
Tuning the action screws has been a thing for a long time. Essentially, you're finding the spot that distorts the action the least. They don't have to be as tight as people think. My savage action screws are barely 30 in lbs, the tang screw being extremely low because that's where it shoots the best.
 
I always knew action screws had a role with accuracy and rifle performance but maybe not to this extent. I think I'm going to add this to my process when working up a new rifle/loads in the future, I'm not going to get too nuts but testing maybe 3 different torque settings might have some very interesting results.
 

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