What if I change stocks after build and load development ?

[Randyc]

Just curious if I do load development , on the stock I have my action and barrel on now, and say I move to a chassis, how will it effect my accuracy?
also if I later change my action and use the same barrel, what effect will,it have?

[WinnieTheBoom]

Differences in headspace will have more of an effect than a stock change will. You may notice a POI shift with a different stock, but groups should be close to the same as long as the action is a tight fit.

[LoneWolf]

I just switched from an XLR Element to a glass bedded McMillan A5. The change.... about .4mils left and .2mils down....

No worries unless the stock you pulled it from wasn't free floated properly. That's about the only thing that might cause a drastic change.

[Randyc]

Thanks guys, I really enjoy hearing all the different opinions, and experiences , I really learn a lot from this gun room. Any and all opinions are greatly appreciated.

[Randyc]

I am on a 110 accustock now , Thinking of putting my barrel on my 12 FVSS-S and to a MDT LSS chassis, I know this changes everything, but I am curious as to how much load development will have to be tweaked , or will it stay close to the same tuned to the barrel?

[Randyc]

Also POI is an easy fix, as long as it hits consistanly.

[LoneWolf]

I've swapped barrels between actions and shot the same loads as well. I just test chambered my current ammo after setting headspace. If you set it a little loose or tight it may change things somewhat.

[Randyc]

I will be using the hornady comparator, to set it as close to the same as possible.
Now might be a good time to give more info.

Barrel is a 24" 1:9 twist
7mm08
hornady brass
berger 168 VLD's
CCI 200 primers
Varget

[Randyc]

Thanks guys , good info from different views.
Will be sure to check headspace and seating depth closely and aim to hit the same mark.

[Randyc]

In case I wasn't clear, the way I replied to Lonewolf, I will be setting headspace with Forster gauges, and a .010 jump to the lands.

[Hotolds442]

We usually just put an index mark on the barrel and barrel nut so you can quickly and easily return it to the exact same spot?

[bsekf]

IMHO When doing accuracy load development, you are fooling with barrel harmonics. Trying to get the barrel to vibrate the same with 1 to 1.5 grain powder difference. So, if you do not change the bedding/pressure on the barrel, there should be no difference in group size. Even a slight change in headspace should make little difference. However, if you change barrels or loads, you get to start all over.

Bill

[geezerhood]

There have been documented increases in accuracy approaching 30%, with nothing more than changing the stock. That could also work the other way if you went from a "good" stock (or stock inletting) to a "bad" one.

[hafejd30]

Your Hornady oal gauge should measure the same with your barrel in the action as it does with your barrel in a vise etc. The gauge doesn't know the difference. It measures from the shoulder of the oal case to the lands. Only thing to check is if your headspace is set proper for the case head to shoulder length. I've changed barrels from one action to another. I run a fired case (fired through this barrel) into the action after setting the headspace with my gauges. If it's tight when closing the bolt then back off just a bit until your bolt closes with slight feeling of the case. Then recheck with headspace gauges to make sure all is well as you can push a case shoulder back if you wrench the bolt down for some reason.

Only way your bullet will have more or less jump is if you machine the barrel or wear the throat down previously to switching. Like I said, your oal Hornady casing doesn't know the barrels even on a gun. I've put barrels on actions and developed loads for that barrel and then moved them to a friends rifles later. I reload for that friend so everything remained the same.

The chasis I've installed on my rifles have made me more accurate, in general. I actually had proper LOP and cheek rest etc. I run 65 in lbs on my action screws on my 3 chasis. Going from an accustock with aluminum bedding block to chasis will probably not change the rifles performance but will allow the shooter a more natural feeling behind the rifle.

[Randyc]

Thanks guys,
wealth of information greatly appreciated.