Need help. Loading 7mm Mag. Can't get consistent accuracy.
- Thread starter Fursty
- Start date
What scope/rings/base? Were scope rings lapped, if applicable? Or do they have nylon inserts like the Burris Signature series? Did the gun ever group any factory ammo? I did read where you've been able to hit 1 moa or better at times. Actually, that's not bad for a factory rifle.
I just took a closer look at those charts you made.
168 Nosler Acubond. RL 26 - 69 Grains did pretty close to 1 MOA and over 3000 fps.
What's wrong with that? Tune the depth a little bit to see if the group tightens up and other than that you are doing pretty good for a rifle like that.
168 Nosler Acubond. RL 26 - 69 Grains did pretty close to 1 MOA and over 3000 fps.
What's wrong with that? Tune the depth a little bit to see if the group tightens up and other than that you are doing pretty good for a rifle like that.
Fursty, Do you have a friend who "can shoot" ?
Spin.
You are right on the 69 with a 3 shot group. But then I tried 68-68.9 in 0.3 gr increments, 5 shot groups hoping to find a good group. Then the 68.9 gr was over 2 moa. I thought it would be better.
I will probably give a shot at seating depth with this powder amount to see if it can be improved.
You are right on the 69 with a 3 shot group. But then I tried 68-68.9 in 0.3 gr increments, 5 shot groups hoping to find a good group. Then the 68.9 gr was over 2 moa. I thought it would be better.
I will probably give a shot at seating depth with this powder amount to see if it can be improved.
South paw
I am going to try a fed primer and compare to groups with Winchester to see the difference.
Next test is going back to the low charge I mentioned before WLRM primer with H4831SC and then 5 shots on sled, 5 on bags, and 5 on sled or bags (whichever was better ) with the fed primer.
I am going to try a fed primer and compare to groups with Winchester to see the difference.
Next test is going back to the low charge I mentioned before WLRM primer with H4831SC and then 5 shots on sled, 5 on bags, and 5 on sled or bags (whichever was better ) with the fed primer.
Fursty said:
Primers tend to make a pretty small difference. The way I like to compare primers is with a chrono and look for low es/sd. It's good that you are doing experiments like this, that's how the craft is learned. Good luck.
Results....
H4831SC.... tried lower loads that had good 3 shot groups.. tried to prove accuracy with 5 shot groups..
Shooting from sled .. 100 yds.. 1.31 moa group
shooting from bags.. 100 yds .. 1.36
using front of sled and bags on rear.. 100 yds.. 1.27
so, initial conclusion.. "this is as good as it gets"
Then back to RL26 with loads at or close to my desired fps.
BUT this time.. measured very closely the JAM length and loaded 0.02" off of jam... seeing if seating helps (I was at about .09 off jam before.)
Results
67.5 gr 1.11moa
68.0 gr 1.07 moa
68.5 gr 2.14 moa
69.0 gr 1.02 moa
AH am I onto something.....? Seating depth....
One more step... going to bed the action and try one more time before writing it off. Ordering bedding material today.
If I have to stay at 0.02" off jam, that round will not fit in my magazine. Is there a way to modify the magazine to accommodate that longer load?
H4831SC.... tried lower loads that had good 3 shot groups.. tried to prove accuracy with 5 shot groups..
Shooting from sled .. 100 yds.. 1.31 moa group
shooting from bags.. 100 yds .. 1.36
using front of sled and bags on rear.. 100 yds.. 1.27
so, initial conclusion.. "this is as good as it gets"
Then back to RL26 with loads at or close to my desired fps.
BUT this time.. measured very closely the JAM length and loaded 0.02" off of jam... seeing if seating helps (I was at about .09 off jam before.)
Results
67.5 gr 1.11moa
68.0 gr 1.07 moa
68.5 gr 2.14 moa
69.0 gr 1.02 moa
AH am I onto something.....? Seating depth....
One more step... going to bed the action and try one more time before writing it off. Ordering bedding material today.
If I have to stay at 0.02" off jam, that round will not fit in my magazine. Is there a way to modify the magazine to accommodate that longer load?
I ran into a similar issue a couple summers ago with a custom 7 mag I had built.
A long drawn out story short, it came down to primers for me.
I was shooting WLRM primers and ended up switching to GM215m primers
and that mad all the difference in the world right there.
I was shooting a Shilen barrel, 1-8 twist and 180 VLD hunting bullets set to just touch the lands.
A long drawn out story short, it came down to primers for me.
I was shooting WLRM primers and ended up switching to GM215m primers
and that mad all the difference in the world right there.
I was shooting a Shilen barrel, 1-8 twist and 180 VLD hunting bullets set to just touch the lands.
Ok, I bedded the rifle and shot a couple of 5 shot groups today. 2 powders, 2 seating depths, but the results were the same. Shooting goups of 1.2-1.7 moa at 100 yards. The factory remington loads had the best groups.
So, now what? Punt to a new rifle?
Upgrade to a new scope?
Hire someone else to pull the trigger?
So, now what? Punt to a new rifle?
Upgrade to a new scope?
Hire someone else to pull the trigger?
A friend of mine got left A Remington model 710- 7 Mag. We ran close to 120 rounds of factory loads through it and never did get it to group better than 3 to 4 moa at 100 yards. He got rid of it. Bought A new Browing X Bolt. Nice looking rifle, have not had A chance to shoot it yet but it looks good anyway!
First off, you have a cheap, recent vintage Remington, which can be problematic. If you have to shoot it at low velocity, then there is no use for a 7 mag.
I own two 7 mags, now, and had one other one. They all shot very well with all loads that I put through them. Try some standard Hornady Interlocks over your re 26, or some re 25. If it won't shoot them, then get rid of it.
I own two 7 mags, now, and had one other one. They all shot very well with all loads that I put through them. Try some standard Hornady Interlocks over your re 26, or some re 25. If it won't shoot them, then get rid of it.
I've a Remington 700 BDL 7mag. Ground down the stub at the front of the stock to free float the barrel, bedded the receiver, lug and tang, dropped in a trigger with 1# pull, 26" barrel, Vortex scope. I use Retumbo almost exclusively, 70grn with a Berger 168 and it constantly shoots sub MOA @ 3002fps, low ES is a plus. I can go higher on the load (around 72grn), but the groups started to open up on me, and I didn't really gain that much more in velocity, plus the ES got higher than I would like.
RL-22 was a close 2nd, but got better accuracy with Retumbo. Don't think I ever tried 4831 powder.....I'm somewhat convinced the fuller the case, the better. And Retumbo gives me that.
RL-22 was a close 2nd, but got better accuracy with Retumbo. Don't think I ever tried 4831 powder.....I'm somewhat convinced the fuller the case, the better. And Retumbo gives me that.
In 1970 PO2 Thomas Treinen a shooter on the Navy rifle team won the 1000 yard Wimbldon Cup with a 7mm Mag. His load was the 168 SMK and 66.5 grn of H4831 with a Remington 9 1/2 M primer @ 3050 fps. Due to his string of 20Vs he was allowed to keep shooting until he missed the V ring. He finished with 32Vs.
There is a good chance your chamber is not very precise. I have a 7mm Mag with a chamber so large fired cases will not fit in a Wilson neck bushing die.
At one time I tried 139 grn Hornady boat tails in 3 rifles and none of the rifles shot the BT as well as the flat base version. Neither 139 grain bullet shot as well as the 175 RN bullet. The various match bullets were also miserable. It is pretty bad when a 105 year old military rifle with issue sights out shoots a heavy barreled single shot with a 12X scope. But that is probably a matter of craftsmanship.
Just remember your 7mm Mag is no better than a 30-30 when you try to take an animal at 600 yards except ....Your point blank 30-30 will probably shoot smaller groups and will not be affected by the wind.
There is a good chance your chamber is not very precise. I have a 7mm Mag with a chamber so large fired cases will not fit in a Wilson neck bushing die.
At one time I tried 139 grn Hornady boat tails in 3 rifles and none of the rifles shot the BT as well as the flat base version. Neither 139 grain bullet shot as well as the 175 RN bullet. The various match bullets were also miserable. It is pretty bad when a 105 year old military rifle with issue sights out shoots a heavy barreled single shot with a 12X scope. But that is probably a matter of craftsmanship.
Just remember your 7mm Mag is no better than a 30-30 when you try to take an animal at 600 yards except ....Your point blank 30-30 will probably shoot smaller groups and will not be affected by the wind.
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Dusty Stevens
Shiner
Youre trying to shoot long range bullets without the correct twist rate. I know nosler said its good but id bet that if you went and got some 140gr ballistic tips they will shoot good just like every other remington 7 mag thru history. And i know you need a new scope if youre using the package deal scope. Dont give up on the rifle itself they usually shoot ok but you have to have a good scope and the correct ammo
timeout
Silver $$ Contributor
I have messed with a couple 783's in 7 Rem Mag. Both shot better than MOA. Hornady SST's in one and Berger HVLD's in the other. That being said, I'm betting you have a luck of the draw lousy factory barrel. I drove myself crazy testing different powder and bullet combinations in a 700 Rem. Finally put a custom barrel on and it shot great. The best money you will ever spend is for a custom barrel. Easy peasy with the 783. Order a prefit, headspace gauge, barrel nut wrench and you're set. Another convenience tool would be a jig to hold the recoil lug in alignment while you tighten the barrel nut. I bought one for a 700 and had it machined to work on a 783 so it works for both models now.
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