shot best group ever

[matts318]

So after getting my crony and finding out that my 270 wsm and 7828 load of 63.5gr was only shooting 2990 fps I decided I needed to do something about it. So I loaded up to 65gr of 7828 and 130 AB and went to the range this morning and my first group was an amazing .176"! I was totally excited to see this gun shoot that good, the previous load would shoot 1" to .75" depending on the day and this load just shot amazing.

Rifle is a Ruger m77 mark II weather warrior and a timney trigger. Now I adjusted the scope for the next group and it opened up to 1.5", Im hoping it was just because I moved the scope, either that or I can only get 4 shots out of my barrel before I need to clean it.

Ok so i need someboby to explain this one to me, my first group with my savage 22-250 and 50gr BT's and 38.5gr of H380 including the fouler shot was .45", second group with 39gr only one shot hit within an inch of my point of aim, one hit 3" low and the other one wasnt even on paper, WTF! This is a gun that will shoot sub MOA with mixed loads and brass, and the brass was nosler brass this time, I have no idea what happened, all guns were very thouroghly cleaned prior to this outing and all groups shot with a cold barrel every shot.

 

[Antelope_Sniper]

I'd say mounting, or poor quality scope.
Last time I had this problem, my scope was loose.
This was also common with many older scopes. After you moved the crosshairs, you had to tap the side of the scope, and take a couple of shots to let the crosshairs "settle". Most quality newer scopes (leupold ect) are now designed with better springs so you don't have this problem. Ocassianally a scope will have a weak spring or two that will cause the crosshairs to jump. If it has a gold ring on the end of it, send it in and they will fix it for free.

 

[jmad_81]

I had a .4" group with that same load out of my 270 WSM. Then I shot it at 200 and it was all over. 64.5 shot into 3/4" at one hundred and an inch and a half at 200. What kind of speed are you getting with this load?

 

[Guest]

Upgrade your barrel to an aftermarket barrel, such as a Shilen or McGowen.

 

[matts318]

I couldnt use the crony at all yesterday because the tripop I had was the wrong size mounting screw so sorry no velocities from yesterday.

The scope on the 22-250 is a 14 power nikon buckmaster, I dont think that heavy gun could kick enough to mess with the springs inside. This gun has never done this, if it ever shoots bigger than an inch it is the shooters fault, it is a consistent performer thats why it was such a surprise.

The 270 WSM has a burris full field 2 3-9 on it, not the clearest glass but good enough, I got it as a package deal with the gun years ago from my friend, I should have shot that other group before moving my scope but it had to move quit a bit to get it centered so I moved it.

Jmad, I know the velocities of 63.5 grains of 7828 was 2990 - 3000 fps with the 130 AccuBond last time, about 200 fps less than the books estimated velocity so I dont think I will be getting much more than 3100 fps out of the bigger load and I am at the max pressure I would want to shoot it at, I just think my 22" barrel is killing me with this slow powder but its what the gun likes so its what I shoot.

 

[JD338]

You have to also consider scope parallax. If not properly adjusted, it will open up your groups.

JD338

 

[woods]

Ok so i need someboby to explain this one to me, my first group with my savage 22-250 and 50gr BT's and 38.5gr of H380 including the fouler shot was .45", second group with 39gr only one shot hit within an inch of my point of aim, one hit 3" low and the other one wasnt even on paper, WTF! This is a gun that will shoot sub MOA with mixed loads and brass, and the brass was nosler brass this time, I have no idea what happened, all guns were very thouroghly cleaned prior to this outing and all groups shot with a cold barrel every shot.

Savages usually have a 1 in 12 twist in a 22-250. That twist should work best with bullets around 60 to 65 gr. I may be that you are overstabilizing the light 50 gr bullet at the increased speed with 39 gr H380. The ability of a barrel to stabilize a bullet increases with speed, so that may also mean that at the higher speed obtained with the 39 gr load, you reached and exceeded the threshold and the bullet was just spinning too fast.

I'm just guessing but I would step up to a bullet of 55 gr or more.

 

[Antelope_Sniper]

Here's another option when you get those WTF results.

Clean you gun, check that everything is solid, mounts rings ect... and retest in the opposite order. Shoot the 39 first, then the 38.5, and see if the results repeat or not. If the results repeated, that would eliminate the remaining varialbles. If not, then it's not the difference in powder charge, but something else.