Accuracy disaster?

[grumpygunguy]

I've mentioned in a couple of other posts that I recently purchased a 110 in 7mm Rem Mag for the purpose of making it a long range hunting and target rifle. I bought the gun at a pawn shop cheap. The first ever group out of the gun having done nothing to it but clean it was about 0.7 inches. That was with cheap Prvi Partisan 175 gr. I bought that just to get it sighted in and was pleasantly surprised. Maybe I should have just left the rifle as is.

I bought a B&C medalist classic and a steel trigger guard. The stick required a little sanding in the barrel channel but not much. The barrel is fully free floated. I also sanded away at the tang area and the tang is free floated. Based on what I've read here I torqued the action screws to 65 lbs. The current trigger is heavy (I'm guessing 5-7 lbs. but I don't have a trigger scale). The scope that came on it isn't much (Bushnell Banner 6-18x50).

I hand load and loaded some 139 gr. Hornady BTSP that I thought would be good hunting bullets over different weights of IMR 4064 ranging from 54.0 to 56.0 gr. Yesterday I shot them all. I didn't even bother measuring the 5 shot groups. The smallest one was probably 2.5 inches and the largest was probably 4 inches. I was shooting from a bench off sandbags. All of the shots felt good.

I have no idea what happened to this rifle. I could chalk it up to just not liking those loads or bullets. I know that 4064 isn't an ideal powder for that cartridge but I just can't believe it would be that bad. So - HELP! Any idea will be appreciated.

[olddav]

The first thing I noticed is the different bullet weights. Have you shot any more 175 grain bullets, or some factory 139 grain bullets?

[grumpygunguy]

I have not shot other 175 or 139 gr. bullets other than what I mentioned. I did shoot some Core-Lokt 150 gr. at the same time I shot the PP 175 gr. I forgot to mention that. I don't recall the measurement of that group exactly but it was slightly over 1 inch and less than 1.5 inches.

[wbm]

I torqued the action screws to 65 lbs

Do you mean 65 INCH pounds?

Wouldn't worry too much about exact torque. One method I use is to take an allen wrench by the short end and tighten each bolt a bit at a time from one to the other until I can't turn it more and go from there with an inch pound torque wrench if I think it needs it. Usually does not.


The scope that came on it isn't much (Bushnell Banner 6-18x50).

Nope it isn't. On a heavy recoil rifle like the 7mm magnum they can come apart quick. Even quicker if you have a muzzle brake on.

[Boudin]

This is exactly the reason I didn't shoot my donor gun before I tore it apart... lol
Do you still have the factory stock? Something quick and easy you could try is to bolt it back in the old stock and shoot a few groups with the same ammo and see if you can duplicate the previous groups.
That way you could eliminate the stock as a problem and focus on your loads.

[grumpygunguy]

Yes on INCH pounds. The scope is crap and will be replaced. Basically it's still on there because it was riding on the rifle when it came home.

I'm beginning to wonder if the 4064 is the problem. I used the Nosler reloading guide and 4064 just because I had some. I've read several posts on other sites today that mimic what wbm says about the burn rate. Almost everyone who has tried the 4064 reports large groups. I will be looking into the Retumbo and RL22. Those seem to be pretty popular for 7mm Rem Mag. Hopefully this is a powder issue and not a rifle issue.

[wbm]

Hopefully this is a powder issue and not a rifle issue.

Hope so too. Would be looking into another scope also.




That way you could eliminate the stock as a problem and focus on your loads.

+1. My Weather Warrior shot better with the Savage synthetic stock than a "non-tupperware" add-on.

[243LPR]

Is this gun used? If so I would give the barrel a good scrubbing,then remove every screw and reinstall it,making sure everything is good and tight. Since you're a handloader try every bullet you can get your hands on,every gun's different about what they prefer.

[olddav]

I'm going to show the limits of my knowledge. I could not find any load data using IMR 4064 with a bullet weight over 130 grains, so I must confess I can't offer anything to this thread. Good Luck.

[grumpygunguy]

olddav - The Nosler website guide shows 4064 used up to 160 gr. bullet. But, I'm pretty well convinced at this point that the problem is powder related. I bought some Retumbo and some 162 gr. Hornady SST so I'll report back on the results with both bullets.

[GaCop]

Looking forward to your report.

[bythebook]

Grump I load for 4 7mm's and they all really like 139 or 140 gr. bullets with IMR 4350 powder.

[grumpygunguy]

Thanks to all for the input. I did not mean for this to become a reloading post but I really appreciate the good information.

I'd like to bring this back around to gun issues instead of ammo issues. The only other variable that I think could cause an accuracy issue is the torque on the action screws. I've read that torque can affect accuracy. Does anyone have any information about the optimal torque for action screws on a Savage in an aluminum bedding block?

[Russmerle]

Thanks to all for the input. I did not mean for this to become a reloading post but I really appreciate the good information.

I'd like to bring this back around to gun issues instead of ammo issues. The only other variable that I think could cause an accuracy issue is the torque on the action screws. I've read that torque can affect accuracy. Does anyone have any information about the optimal torque for action screws on a Savage in an aluminum bedding block?

If you go to this link https://savagearms.zendesk.com/forums/21996616-Frequently-Asked-Questions it should have the answer. I can't pull it up but it has a most frequently asked question of "What is the torque spec for action screws?"

From observing the link at the Google page, it looks like it quotes 30-35"lbs for synthetic stocks and 40"lbs for accustock. I think those are some good specs to start at since the accustock is aluminum.

I really think you should shoot some more manufacturer match rounds, after re-torqueing, to determine if it truly is the rifle (if you haven't done so already)... And like some have already mentioned here, torque each screw a little at a time until they're at spec.

[Rdot]

FWIW my model 11 in .308 will only shoot 180 gn. bullets the way I feel it should. Anything else I feed it opens up my groups to 2"+. I wouldn't discredit it as an ammo issue just yet.

[WinnieTheBoom]

Need to isolate the issue first and foremost. Even if it means going back to factory ammo to use as a point of reference. This way you're not throwing darts in the dark and just hoping for the best. All good info here, but start with the basics.

Give the barrel a good cleaning, maybe try going back to the original stock, try different ammo (both factory and handloads) to see what seems to work and what doesn't work. 7mags have pretty good barrel life so I wouldn't suspect that to be the issue - issues like this just take time and patience. Just keep in mind that as long as you're doing your job as the shooter, you should be able to sort out the issue pretty quickly.

Plenty of of good recommendations to get you started in the right direction. Try some of them and report back.