Tikka T3 Stock swap and reloading

OK, I took the stock off the action again, and found a single pressure point inside the barrel channel that initally did not show up, but a rub mark on the cerakote shows at some point the barrel is contacting the stock about 4 inches up from the receiver. So a little work with the box cutter knife shaving it away and off to the range today to see what happens from here.

I also will be doing the ladder test to see if there is any more data to be found from that method. My other question though is this: without a chronograph, will the ladder test still be worthwhile (I expect to see two sweet spots in the 20 shot test).
 
I have a T3 (.308) which is prone to copper fouling. Group sizes open up considerably after 15-20 rnds, however if the factory loads are still shooting consistantly this would not appear to be the most significant problem.
 
OK, latest trip to the range with factory ammo cleared up a few things.

First, my action screws were a bit tight.

Second was the rings on my scope may have been a bit loose.

Third, my barrel heats up after three shots spaced at least 2 minutes apart with the fourth shot almost consistently going 2 inches high and to the right at 100m. The first and second shots usually touch, the third will go low and to the left, and the fourth high and to the right. I had a friend shoot it as well, and his groups did similar things, both with handloads and with factory stuff.

Fourth, there was a small point of contact in the barrel channel that was not present on the walnut stock, only on the synthetic one. For the life of my I cannot figure out why Tikka would have moulded a cradle into the barrel channel, specifically sized to the barrel. When I took the action out of the stock and really looked closely I found two scuff marks on the barrel, in line with where they would have contacted the stock on this cradle. Out came the sharp boxcutter knife and shaved those little tabs away. Next, I scraped out a bit of the stock where the action fits into it, as with the Cerakote on the action, it was a couple of 16ths wider than before. I also cleaned out the slot on the bottom of the receiver for the bedding block to fit into to make sure the Cerakote was not causing an imbalanced fit.

Prior to these changes, I was fed up with 40 handloads wasted, a bunch of stupid questions on the internet, and a serious doubt in the changes made to my previously sniper-accurate hunting rifle. Now I am back in business, and will be back at the reloading bench this week.

Next step will be to go out and shoot a ladder test group of 20 rounds. I will post up here to see how it goes.
 
Finally an update, which I realize you all were waiting for with baited breath (right). Ladder test showed signs of promise at the 53.4, 53.7, 54.0 and 54.3 grain weights of h4350. Next up was loading 4 each of 53.4 to 54.6. The load I settled on was 54.0 grains of H4350, with a slight change in the COAL to 3.30". The reasoning on this was a sub MOA group of 4 out to 200m off a front and rear bag rest. The chronograph velocity put that load at 2645fps on a 15 degree C day.

The end result was a one kneeling shot kill on a moose at between 70 and 80 meters, going quartering away. The bullet mushroomed as advertised, going in just behind the left shoulder and lodging just under the hide on the off shoulder. The bullet will be weighted on a scale for weight retention soon. Looks like a minimum of 70% retention.
 
You switched from a wood stock to the plastic stock, I have 3 of these and the presure point does not exist on the wood but does on the plastic. If you look close ont of the cross ribs about 4 inches from the reciever sticks up higher and does craddle the barrel. On my 204 it does not seen to make a difference, on my 260 I sanded it out to free float. Good luck. And if you want to sell your wood stock let me know, after you get it figured out!
 
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