7mm mag recipe - now with Range(pics) report #2 finally
- Thread starter jacky
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I use IMR 7828 with the 160gr Accubond. I used the 160gr Partition data, which gives starting load of 62.5gr and max of 66.5 grains. The book velocity for the max load is 3090fps out of a 24" barrel. I ended up at 66.0gr and .75" groups at 100 yards. I used Winchester brass and 215 Match primers. I didn't chronograph the load, but my rifle has a 25.6" barrel, so I suspect it should be around 3000-3050fps.
762nato said:
Thanks
I went with this data and I am going out to the range tomorrow ( hopefully)
I wont chrony the load yet but I loaded up 5 rounds each from 56 grains to 60 grains. Its a start and once this is done I will do it again going plus or minus
.5 on either side of the most accurate load. It should work well I assume since every other bullet works excellent with this powder in my gun, including the 140 grain accubond.
Jacky
762nato said:
Cool. I use a free program called Point Blank. It will also do trajectory and energy info. I would be interested in seeing how the two programs compare. I will let you know my final load. It won't be from this batch, unless I get real lucky, which is what happened with the 140 grn Accubonds. I will be able to fine tune the load to a tenth of a grain next time out. This time out is just to get the range for the fine tuning
Jacky
Ok so I went out shot 3 rounds each with 57 grains to 60 grains (160 grain Accubond using my Tikka 7mm mag) Now none of the results are bad but looking at the groups I think 60 grains is the way to go and it leads to another question. Check it out.
57 grains IMR4350
58 grains
59 grains
60 grains
Now above it was listed by 762Nato that 60 grains was max. I did not see one sign of pressure at 60 grains. However, in the fine tuning of this load is it safe to go over 60 grains ? Should I try and go to 61 grains in .1 increments. If I do this the way I usually do I would load up three rounds starting at 59.5 grains and go in .1 increments to 60.5 grains. What do you think ?? I might have been able to go to 62 grains, who knows ?? Does anyone have the CUP measurement for the 60 grains of IMR 4350 powder using the 160 grains Accubond ?? Thanks in advance.
Jacky
57 grains IMR4350
58 grains
59 grains
60 grains
Now above it was listed by 762Nato that 60 grains was max. I did not see one sign of pressure at 60 grains. However, in the fine tuning of this load is it safe to go over 60 grains ? Should I try and go to 61 grains in .1 increments. If I do this the way I usually do I would load up three rounds starting at 59.5 grains and go in .1 increments to 60.5 grains. What do you think ?? I might have been able to go to 62 grains, who knows ?? Does anyone have the CUP measurement for the 60 grains of IMR 4350 powder using the 160 grains Accubond ?? Thanks in advance.
Jacky
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its possible to work over the 60.0 grs., but keep in mind you're pushing the limits with 4350, which is a fast burning powder in the 7mm Mag, especially with heavier bullets.
If you got a chrony or can borrow one, work up slowly, but dont go much past 2950-3000 fps with a 24" tube with them 160s & 4350 62-63 grains is usually considered the max with the slower burning IMR 4831
I personally would buy some RL22, IMR 7828, H4831sc, RL25, or H1000...
If you got a chrony or can borrow one, work up slowly, but dont go much past 2950-3000 fps with a 24" tube with them 160s & 4350
62-63 grains is usually considered the max with the slower burning IMR 4831I personally would buy some RL22, IMR 7828, H4831sc, RL25, or H1000...
todbartell said:its possible to work over the 60.0 grs., but keep in mind you're pushing the limits with 4350, which is a fast burning powder in the 7mm Mag, especially with heavier bullets.
If you got a chrony or can borrow one, work up slowly, but dont go much past 2950-3000 fps with a 24" tube with them 160s & 4350
I personally would buy some RL22, IMR 7828, H4831sc, RL25, or H1000...
This is pretty much what I woudl say, too.
I've exceeded lots of published max loads with a 7RM, but I have a chronograph, and I've measured case heads for expansion.
There is nothign wrong with that 60gr group, though. If it is consistent, there relaly isn't much need to exceed that powder charge in a big game rifle.
Be aware that the temperatures are quite cool at this time of year.The loads that show no pressure signs could be very hot when the warmer weather arrives.Also,I do not attempt to judge accuracy based on a single group with each load.Once I see a load that shows potential,I fire several groups to verify the accuracy.
stubblejumper said:
For sure. Those groups were just intial loads in the development of a good load.
The 60 grain load has potential and I plan to chrony it next time out. I don't think I would exceed 60 grains by a lot because as stated above it is cold right now and when spring bear hunting this year it will be warmer
I think I will make some loads that go from 59.5 to 60.5 and see what happens. If I can get a intial grouping from those I will load up a few and check consistancy. Usually if a three shot group looks like the 60 grain group the load is good it is just the shooter that can screw things up.
Jacky
Alright so I finally got out and chrony'd this load. I stuck with 60 grains of IMR 4350 and the 160 grn Accubond. The average velocity was 2886 fps.
Here is a 6 shot group at 100yrds
And here is a 4 shot group at 250 yrds.
The shooter could have done a bit better but all in all I am happy with the load. I thought about going higher to get more velocity or even trying ( once again) RL 22 as per Tod's suggestion, but at 2886 fps there are no pressure signs ( an it was about 14 deg warmer) the load groups well and the bear I plan to kill this spring will not know how fast the bullet was going when it hit him
Jacky
Here is a 6 shot group at 100yrds
And here is a 4 shot group at 250 yrds.
The shooter could have done a bit better but all in all I am happy with the load. I thought about going higher to get more velocity or even trying ( once again) RL 22 as per Tod's suggestion, but at 2886 fps there are no pressure signs ( an it was about 14 deg warmer) the load groups well and the bear I plan to kill this spring will not know how fast the bullet was going when it hit him
Jacky
jacky said:Alright so I finally got out and chrony'd this load. I stuck with 60 grains of IMR 4350 and the 160 grn Accubond. The average velocity was 2886 fps.
Here is a 6 shot group at 100yrds
And here is a 4 shot group at 250 yrds.
The shooter could have done a bit better but all in all I am happy with the load. I thought about going higher to get more velocity or even trying ( once again) RL 22 as per Tod's suggestion, but at 2886 fps there are no pressure signs ( an it was about 14 deg warmer) the load groups well and the bear I plan to kill this spring will not know how fast the bullet was going when it hit him
Jacky
Jacky,
Those 2 groups have a lot of vertical in them. If you were on a steady rest, this shouldn't be with the right load. Many times increasing the charge will result in less vertical. You say you have no pressure signs and the temperature was warmer, you may want to go up 2 grains and try again.
But as you said, you do have a minute of bear load already.
NormB
