7 Rem mag R26 load data?

[Truk505]

I've got some R26 and 175gr bergers and was hoping to find some load data for the 7 Rem mag. Ive never loaded for the 7 Rem mag so if anyone has another suggestion I'm all ears. I have some imr 7828, h/imr 4831, h/imr 4350, R22 and probably some other stuff that might work too.

 

[Capt RB]

I started my ladder @ 65grn of rl26. I'm running the 180 hybrids though. I was using 3.6 coal to start. I haven't been able to shoot it much and I don't see shooting much before next Wednesday. I went up 4 grains in 1/2 grain increases. Primers were just starting to flatten. I have not done any seating tests yet and I think it should help. Below is what they tested with the 175's unfortunately RL26 isn't on the list but Rl33 is along with 7828 and MRP.

http://www.bergerbullets.com/pdf/7mm-Remington-Magnum.pdf

 

[284saum]

I can't help much, but 66.6grs RL26 under a 160gr Nosler Accubond is doing 2920 fps in a 24.4" Tikka 7mm Rem Mag. Not a hot load

 

[codyadams]

I have done quite a bit of load development with the 180 VLD and Reloder 26 in a factory Remington 700 long range. I'll give you my data before and after HBN coating....as always, WORK UP SLOWLY. Your gun could be much different.

Sorted Federal Brass
CCI 250 Primer
180 Berger HVLD
.015" off the lands in SAAMI chamber (around 3.500" if I recall....)

64.5 - 2793/2800/2794 - avg 2795
65.5 - 2894/2887/2892 - avg 2891
66.5 - 2923/2924/2936 - avg 2927
67.5 - 2987/2982/2998 - avg 2989
68.5 - 3018/3025/3027 - avg 3023

At 68.5, there was possibly a very faint ejector mark and but heavy bolt lift, pressure was getting up there I think because primers were slightly cratered. I didn't go any higher, because accuracy was just starting to go down anyway. We stuck with a load of 67.8 for a while, and was around 3015 fps. Brass had 4 fireings on it with this load and was fine.

Next we HBN coated them, and had to work up charges a little. DO NOT TRY THE TOP LOADS. They were hot even with HBN coated bullets. They would likely lock up a gun with naked bullets.

Federal Brass
CCI 250 Primer
180 Berger HVLD, HBN coated
.015" off the lands in SAAMI chamber

67.0 - 2955/2966/2978 - avg 2966
67.7 - 3015/2996/3002 - avg 3004
68.4 - 3035/3037/3058 - avg 3043
69.1 - 3069/3075/3074 - avg 3072
69.8 - 3130/3133/3131 - avg 3131
70.1 - 3158/3151/3143 - avg 3150

KEEP IN MIND THESE ARE HBN COATED, SO CREATE LESS PRESSURE. So I certainly found max on this work up. I started seeing pressure at 69.8 in the form of light ejector marks. But accuracy was extremely good, under half MOA, and was very consistent with only 3 fps e.s., and they were STUPID fast, so out of curiosity I tried the next load. I found that even with only .3 grains increase pressure signs raised significantly. Heavy bolt lift, shiny ejector mark, and cratered primers. Accuracy was still around half MOA though....just completely unsafe pressure.

We ended up loading 68.6 grains, and they are going 3050 fps, magneto speed and drop verified to 1660 yards. We have 2 more fireings with this load, primer pockets still tight. Here is what I would do to give myself a margin for saftey with a gun I don't know with the 175's:

Start at 64 grains or less, and work up 1 shot and 1 grain at a time, while chronographing, until you find your max pressure, you will find your max with under 6-8 bullets, I almost guarantee it. Then you can work your loads in .5 grain increments or so around the velocity range you want to be in that is still under max pressure.

Should get you close. Hope this helps.

 

[Truk505]

Thank you, that is exactly what I was looking for. Great information.

If you have any other suggestion as for what powders I should also try, let me know.

Thanks again.

 

[codyadams]

Thank you, that is exactly what I was looking for. Great information.

If you have any other suggestion as for what powders I should also try, let me know.

Thanks again.

I tried H1000, it was about 30-50 fps slower, and not quite as accurate in this specific rifle. Yours may like it though. You may consider it if you hunt in extreme temperature swing areas, or travel to vastly different climates to hunt, as some people report temp sensitivity with RL 26, though in my .260 AI, this 7mm mag, and two 6.5x284's we have not noticed enough velocity swing to be concerned about. Our hunting temps range from single digits during late season elk to about 80ish degrees for August pronghorn hunting.

Most the bad reports I have seen are people seeing pressure spikes over 85ish degrees. Again though, I personally have not experienced this during summer prairie dog shooting, where temps can get a touch over 90 here in Wyoming. I would get a load with Reloder 26, and try it in your hottest temps to see if there are any issues. I don't think you will, but I have been wrong before and certainly will again.

 

[Truk505]

Thanks for all your help.

 

[Truk505]

Does anyone else have any expirience with r25 or retumbo?

 

[Capt RB]

Does anyone else have any expirience with r25 or retumbo?

My brother's 7mag loves retumbo and the 162 amax. I did a ladder in late Sept or early Oct with Rl26. I showed a bunch more speed and interestingly a node near the top. He didn't want to play with it before deer season though. His is a factory tube so 162/168's are about the biggest high bc bullet he can use. Rl25 in most things I ran it in shot well but never tried it in a 7 mag. 300wby 270wby seemed to shoot very fast from drops but this was early 90's before I owned a chronograph. Only the 300 was shot past 450 on purpose regularly though. I tried it in the 243 about 2008 with 105 amax's in a 9 1/4 tw wouldn't group as well as h4831. That had a pretty big speed advantage and a primer change may have helped but it didn't seem worth the effort at the time.