escaped to the hill today with the rifle "m70 winchester 24" barrel".
129gn hornady sst's 75gn H870 @3050fps
100yd grouping was about 1/2 " 300yd group was about 12"
any thoughts on this would be appreciated!

regards
griff

how are you gunnin up?
Are you shootin off a bag rest or a pod?
What scope are you usin?
Was it windy?
You definitely not holdin yer mouth right.
Pokin a little fun.
I shoot the 140 sst out to 500yds I use H450
9 1/2 rem mag primer
3117f/s 26" barrel 1:9
shoots 6" groups at 500 1" at 100
Dave

hivelocity,
used both the pod and sand bags, burris black diamond scope with signature rings and leupold bases, glass bedded into bell & carlson stock!
the only thing I didn't do looking back in retrospect was let the barrel cool down sufficiently..

regards

griff

quote:

Originally posted by griff:
hivelocity,
used both the pod and sand bags, burris black diamond scope with signature rings and leupold bases, glass bedded into bell & carlson stock!
the only thing I didn't do looking back in retrospect was let the barrel cool down sufficiently..

regards

griff

WIND??

heat may be a minor factor, but I would'nt think to that extreme
1 foot ? I would test it again making sure I had a good sand bag rest front and rear, i use a fairly good hold on mine even with the 26" barrel it jumps pretty good
If the trigger is to heavy or you are not getting the rifle back into the same position shot to shot. was the group vertical or horizontal.
I have had a couple m70 where the stock were just terrible . one in 25/06 had a ridge running down the center of the barrel channel.
you have restocked your and the only other thing might be the ammount of torque on the action screws. That would also show up at a 100yds and your doing great there.

The most typical cause for that amount of dispersion between 100 and 300 yards would be wind. You'd be surprised how much difference wind can make, particularly if your first 100 yards is somewhat protected and the remaining 200 yards is subject to stiff and inconsistent winds.

Are you SURE your rings and base(s) are absolutely tight??
I'm assuming your barrel is free floated.. have you run a piece of paper up and down the barrel to make sure..?
I remember several years back I tried a Burris scope on an '06 I had and it worked well for a little while.. But one day I found the rifle was shooting all over the place and then discovered a 'rattle' inside the scope.. Took the scope back to the gunshop and got another one.. whaalaa.. back in business again..

I'm inclined to think this problem is scope/base related.. It sounds like you are an experienced shooter so no need to cover the basics.. That is the only thing that could cause such extreme grouping given the rest of the rifle is sound.. and, you are shooting on a calm day.

Griff, quickload says that this a compressed load, and all powder doesn't burn in even a 25" tube--just checked 25" to add a little cush to your 24" spec.

I'm not sure what all that means, I'm a quickload newbie to the max, but my number one hunting partner has a .264 Win Mag,and had the same issues. It may have just been luck, but all his ills were cured when we reduced the powder charge by about 3 gr, which kept it from being a compressed load.

Also, I think that SST is a boat-tail, which can get squirrely on top of a compressed load.

Just a little info FYI--hope it helps

Regards--Don

Griff, my assumption the way your question was posed is that you have already eliminated other potential variables and are experiencing a marked disconnect in the (presumably consistently) good accuracy at 100 yards and poor accuracy at 300 yards. Therefore, you are not suspecting a problem with your scope, bedding, or loads, other than questioning if the 129 gr SST somehow loses stability or in some other way deteriorates in accuracy.

Is this the case?

fish 75grs H870 will give 100%load density.
with rem, win, fed, and lapua brass.
the sst bullets for 264 are pretty long.
boat tail start to perform at 300yrs and beyond.
I say the wind bad trigger or shooting skill at that range.

Hivelosity, sounds right to me. I have seen boat tails on compressed loads act funny, but they certainly seem to do better at longer ranges as a rule.

Regards--Don

Griff,

If shot in order 100m fist, 300m last I would hazard the following;-

fouling
unsuitability of target for precision aiming at 200yards
wind

I recently went from 0.75" at 100 to 3" at 200 - wind and aiming point being unsuitable.

Adam

Griff

It's to bad that you don't have a 26" barrel on that gun because that is what really makes the .264 click. That H870 is way to slow for your rifle. Gain some MV and probably some accuracy switch to 4831 with that bullet.