Please help me understand my shot groupings

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My setup:

Savage 10TR
Factory synthetic stock
Caldwell bipod
Vortex CrossFire II 4-12x40 AO
Coretac muzzle brake
147 gr reloads (campro)
180 gr reloads (speer grandslam)

The 10TR has a heavy barrel. How many shot strings will it take for the barrel to heat hot enough to start affecting accuracy? This was shot at a 100m distance.

I still have a long way to go in improving my trigger pull, breathing technique and proper positioning behind the rifle.

The first cold shot was trying to aim at the center of the target. I was hitting the ring next to the bullseye. I tried to concentrate more on my trigger pull and breathing techniques and I was able to start hitting the bullseye (center).

I then set my sights to aim for the right target. I got one bullseye, but the rest ended up in close groups at around 10-11 o'clock from right side bullseye mark.

What I am a little perplexed about were my attempts to shoot the red dot on the far left. I was missing the mark. I was thinking that the barrel could have been getting hot and starting to loose accuracy?

The weather today was rainy and cool (about 9 degrees c) when I shot these in the afternoon. You can see that there were a couple of flyers at the top left corner.

8Mml6oy.jpg
 
I thought this was another SKS accuracy thread. Try again with one group per target only. Print your own of you have to. Once you're on target never change your zero between targets. Also, different bullets will have different zeros, so please don't shoot two different loads on the same target.
 
I don't think that the campro would really be a precision bullet. May I suggest that you switch to something the the 178 gr hornady or the 175 gr sierra matchking. And like the poster noted above one group per target.
If you're new to shooting off a bipod don't even bother too much with load development at this point. Get something that will shoot and keep putting lead down range until groups start to tighten up.
 
I didn't read much past the listed projectiles. Bulk projectiles are not worth your time if you're chasing sub-moa accuracy (been there).

I would switch projectiles to 168/178gn BTHP and redo your load development. Try to shoot from a rest, not the bipod. The shooting part is easier than you think and I'm willing to bet that most of your problem lies with the ammo.

My HB .223 starts throwing groups after the 12th shot or so. I have targets/data from several trips to confirm. Would suggest shooting a couple foulers, one group then cool and repeat. Have not tested my .308 for this yet.
 
I would advise our inexperienced customers to dry fire until trigger work is good. Just find a small target at 3-500yds where one can just fit the crosshair on, at highest mag. If the crosshair moves in the slightest...keep practicing. Once that is mastered I would say try some good match ammo. We have very little choice where we live but have fantastic results with Hornady Match 168gr bthp ammo.
Shoot less evaluate more. Every shot should be evaluated good or bad. 308s are easy to get to shoot. Once one has reliable results with factory match ammo I would suggest match bullets for hand loading 155/168/178. I like 168 for hunting and informal target or long range plinking out of my 308s.
edi
 
Agree with EJG. Get a baseline using match ammo. I used Fed GMM 168 gr when I had my 10tr and it was capable of putting bullets in the same hole at 100m.
 
I've tried the Campro projectiles you've mentioned..... Lets just say they aren't even decent for "plinking" in a fresh off the shelf M-305..... "Terrible" is another word I've heard them described as...

Grand slams are noted for their superior performance on game animals. They are not noted for superior accuracy on paper.

I sold my 10TR, but it liked Federal GMM 168gr ammunition and REALLY liked Hornady Superpeformance Match 168 A-max ammunition.

That rifle also seemed to like loads well above published max loads or very very mild loads near the bottom of the published load data. One very mild load of 40.5gr of H-4895 @ 2460 fps shot Sierra 168 SMK's into 1/2" at 100y and held them to MOA(ish) out to 600 meters.... The problem was they were too slow to really reach out past 750-800y.

The other advice in this thread as far as targets is very good advice. Personally I like the "redfield" style sight in targets. I really doesn't matter how big your retical is if you are aiming for the corner of a diamond. Aim small miss small....
 
You have received great advice but one extra thing that may not have been mentioned is to insure all your scope, mounts and action screws are torqued to the proper weight. I had a similar problem and found the people who had mounted my scope blocks and scope didn't tighten up the rear mount block. The slight wiggle sent my shots left and right.

The gun you have is an accurate one if everything is tight and you do what is necessary to get good groups. I have a Rem M700 .308 SPS that shoots under 1 MOA with Federal 150gr spitzer soft points so I wouldn't get to carried away with burning up a lot of big dollar loads.

Once you can get 1 MOA with stuff like that then get some match loads.

Good luck.

Eric
 
ericrose said:
You have received great advice but one extra thing that may not have been mentioned is to insure all your scope, mounts and action screws are torqued to the proper weight. I had a similar problem and found the people who had mounted my scope blocks and scope didn't tighten up the rear mount block. The slight wiggle sent my shots left and right.

The gun you have is an accurate one if everything is tight and you do what is necessary to get good groups. I have a Rem M700 .308 SPS that shoots under 1 MOA with Federal 150gr spitzer soft points so I wouldn't get to carried away with burning up a lot of big dollar loads.

Once you can get 1 MOA with stuff like that then get some match loads.

Good luck.

Eric
Click to expand...

Same deal here. Gun shop didn't tighten down the rail properly, it didn't seem loose but would move a little on recoil, probably sent $200 worth of ammo down range before I figured it out. This was on a Remington 7005R, same gun shop also tried to center my barrel by putting gorilla glue or something like between the barrel and the stock. I ground all that out, and skim bedded the rail and torqued all that down to spec, this improved the gun from producing 2-3" groups to < 0.75" at 100m.
 
If you are changing your sights between groups, stop doing that. Just get a zero, and when you have done a little dry firing, load 5 rounds of 1 ammo type and shoot a group at one of your target dots. It doesn't matter where the group forms, you're just trying to see what ammo groups well, or best, out of your gun.

Leave your sights the same for each string of 5 rounds, and try and give yourself a few dots to shoot at all on the same plane a few inches apart so no group overlaps. Hold center of the dots, and shoot your groups.
Take your time, and don't worry about the results until you are done. Now you can evaluate some good data and see if you have a load that shoots, or keep trying until you find one that does. Once you find a load, you will reset your zero for that load. That rifle with most good factory match ammo should shoot well under an inch at 100 yards.

All of the advice you have received is great, make sure all screws etc are properly torqued, use a rear bag, a front rest or bipod, good position, watch the wind gusts. Shoot on.

Let us know how things go.
 
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168Gr SMK over 42.7 grains of Imr4895 gives me tight groups, just recently had really good luck with TAC (can't remember the weight offhand and don't have my load log handy) under Nosler custom comp 175Gr
 
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