The cause of poor accuracy was the stock? Maybe……..

[northny]

I picked up a new Rem 700 three years ago, a varmint barrel SPS in .223 Rem. I planned to use it for PRS practice when working at positional shooting at shorter distances ( say 300 -400 yards) when I couldn’t get to a long distance range. Why put wear and tear on my 6.5 CM barrel and use up scarce components plinking short range?

I got the rifle on clearance, and although I bought it new in 2021, the barrel date code had it as produced in 2015. It came from a major retailer that didn’t have a major focus on firearms, (and who now is out entirely of firearms.) I have full faith it was exactly was it was billed as….new old stock.

Usually with one of these,I drop in a Timney trigger, add a useable scope, a little load development and I’m at sub 1 moa. The plastic SPS stock also gets modified with bottom metal for AICS mags ( which includes pillar bedding the action) and the barrel free floated.

Not this one. After my usual mods, this one hung out 1.2” to 1.4 inch. Nothing terrible but nothing good. Bore scoped it, looked over mechanics and saw nothing amiss. Rechecked all the screws, nothing. Off came scope and rings and 20 moa one piece base. Nothing loose. Put it back together. Same thing different day. Switched scopes with another rifle, the scope was not the issue. I was 200 rounds into this with no joy

So the other day I put together a group of hand loads that should work. New Winchester brass, Nosler Sierra and Hornady bullets, Varget and Benchmark powders. I had thirteen sets to test, my feeling being if none of these shot well, the barrel was crap. So I went to the range this morning to test, and I planned to spin the barrel off this afternoon then order a new one. (I was on line last night spec’ing out the new barrel. 1:8 twist, 24” long, I was looking forward to ordering it)

Before going to the range this morning, I switched the stock out to an older Fajen laminate stock I have, pillared with AICS bottom metal.

Now this morning everting changed. everything is now shooting sub moa. ( two 5 shot groups 100 yards)

50 g Noslers. .44” / .54”
55 Noslers. .75” / .71” / .72” ( three groups)
50 Hornady. .80” / .89”

So after my tenth sub moa group of the morning, I’m wondering if the stock swop was cause of the improvement? So having shot only half of my testing plan, time to switch things up. For each rifle I have a log book of what I have been shooting, and the results. Targets get entered after the range session. Looking back, the worst performing load I had shot ran just under 1.4 inches ( four five shot groups, 1.3 - 1.4”, two groups on two different days). CFE powder, pmc or Hornady brass, 50 grain Hornady zombie something bullets that I got in a 500 pack when that was all I could find)

As Luck had it I still had 20 rounds of that same batch with me, 10 each of the PMC brass, 10 in Hornady brass. The results today were .80” / .97” / .87” / .96”. A vast difference from 1.3”

At that point wind was starting to pick up so I called it a day

In spite of the data, I have a hard time accepting a stock swop resulted in that amount of change. I am going to have to put the old stock back on at some point and try it. Of course it could be the stock is ok, but maybe last time I mounted rifle in the stock I just screwed it up. I have a routine I usually use to insure the back of the receiver lug has full contact back to the stock and that the action screws are tightened incrementally. The way I pillared bedded it the receiver should then set stress free in the stock. But something sure wasn’t right.

So that is today’s range report. Always something new to learn

 

[Mountain]

Stock interference and/or lack of stability can indeed have a very significant effect on accuracy. I'm a bit surprised you were not aware of this, though maybe that's not such a hassle for many modern stocks. For sure, your typical chassis stock isn't going to cause problems.

I shoot a fair amount of vintage matches including M1 Garand and Vintage Sniper. One of the most challenging aspects of accurizing these rifles is getting the stock fit correct. Also the action screw torque can have a significant effect depending upon the rifle.

 

[Dennis in MA]

What was teh original stock made of? Wood? Plastic? How was it bedded. I wonder if it was just crooked or something. Misaligned somehow and pulled a twist on the bbl constantly. It's amazing what a bit of plastic or wood can do to move a bbl.

 

[alx]

I am not a PRS shot, but I wonder how a stock has any effect on static (off a vice for the lack of better analogy) grouping. Rifle hardware-wise barrel, scope/ sight attachment and bolt are the -only- three aspects that matter. So... I fail to see the correlation to the stock.

Feel free to educate me of course lol..

 

[LuvDog]

I've seen just the torque on the action screws have an effect

 

[Rockrivr1]

I've seen just the torque on the action screws have an effect

Yep. Was at a beginners PRS event a couple years ago and within the first couple shots out of my Savage Precision Rifle the retaining screw for the stock to the barrel came loose. My zero was way off at that point and I didn't score a hit all day. Got home and found the screw loose. I've always been leery of using lock tight on my guns, but I do after that incident.

 

[peter_nh]

There is a reason why sharpshooters go to a lot of trouble to "bed" the receiver/action to the stock, typically using glass filled epoxy. It is to remove sloppiness and any relative movement, which can change the trajectory upon firing. Note that you want to use a release agent so the action is not actually bonded to the stock. Synthetic stocks are usually better in this area as they do not shrink and swell with humidity changes like wood does.

 

[Taipan01]

Same thing happens with the lowly 10/22 and the action to stock bolt screw. I start them at 12 inch/pounds and test the groups up to 25 inch/pounds. You'll see the groupings opening and closing. My newest likes 14 inch/pounds for CCI mini-mags the best. May change if I switch to Agulia or another brand.