7mm rem mag help

[AbeS]

Has anyone ever tried to load 7mm rem mag with h4350 and large rifle primers not magnum primers? What kind of accuracy did you get?

Seekins precision in 7mm rem mag 26” barrel with ec tuner break 1:8 twist
Nosler brass
Cci br2 primers
Hodgdon H4350
Hornady 180gr Eld-m G1 Bc. 796

This is what I have available to me.

Worth the try or waste of my components? Accuracy being the main goal. 0.5 moa or better achievable?? North Dakota weather it’s gonna get cold

 

[IALoder]

There's load data on hodgdon for H4350 and a 180 in 7mm Rem Mag, LR Primers should do okay. Accuracy is definitely possible, but it'll be slow in the velocity department.

 

[FLIGHT762]

If this is for a hunting rifle to be used in the North Dakota cold, Magnum primers are a good idea. If you're just target shooting, you can use the regular primers. It's the really cold temps where you'll need a magnum primer.

 

[AJC1]

What is the case fill using that powder. Lower charge densities would make it even a larger problem for reliable ignition. In the few tests on the subject I've seen staball 6.5 was very bad in this senerio. In a have to make it work being pocket warm may help.

 

[Driftertank]

H4350 will be quite a fast burn rate for that bullet weight. It can be done, of course, there's data available. I sort of feel like it might be hard to get consistency -and therefore accuracy- out of...most data I dug up says a max charge of around 55-56gr. I feel like that would leave a lot of airspace in the case, which often means somewhat inconsistent ignition. I may see what that case fill looks like when I get home from work, just from curiosity, since I have the powder and cases for that combo on hand.

And your post says CCI BR4...Did you mean BR2? You do say Large Rifle...just making sure I'm tracking with you. I sort of feel like low brisance and single-digit temps might not play nice together.

I wouldn't go so far as to call it a waste of components, particularly if that's all you have on hand...after all, some ammo is typically better than no ammo. But I would be... let's say pleasantly surprised, if that combo gives good accuracy results in the cold. Magnum primers would likely improve matters a bit, but watch for pressure...fast burn rates for case volume often mean pressure spikes early in the burn, so pressure increases could be sudden.

 

[AbeS]

H4350 will be quite a fast burn rate for that bullet weight. It can be done, of course, there's data available. I sort of feel like it might be hard to get consistency -and therefore accuracy- out of...most data I dug up says a max charge of around 55-56gr. I feel like that would leave a lot of airspace in the case, which often means somewhat inconsistent ignition. I may see what that case fill looks like when I get home from work, just from curiosity, since I have the powder and cases for that combo on hand.

And your post says CCI BR4...Did you mean BR2? You do say Large Rifle...just making sure I'm tracking with you. I sort of feel like low brisance and single-digit temps might not play nice together.

I wouldn't go so far as to call it a waste of components, particularly if that's all you have on hand...after all, some ammo is typically better than no ammo. But I would be... let's say pleasantly surprised, if that combo gives good accuracy results in the cold. Magnum primers would likely improve matters a bit, but watch for pressure...fast burn rates for case volume often mean pressure spikes early in the burn, so pressure increases could be sudden.

yes I meant to type br2. Thank you for pointing it out. I fixed it and thank you for all the information. You have validated some of my concerns, case fill delivering consistency being one of them. 56gr compared to 69gr for max loads and off course ignition in colder temps with regular lrp.

Thanks everyone for the replies. All your advice helps me quite a bit. I take what can get.

I would like to use it for hunting early November here in ND but after that I would like to shoot at 600 and 1000 and see the best accuracy I can get at those two ranges. I was real excited when I found a barrel for the rem mag chambering in 1:8 twist. I’ve always thought that if a 284 win sends a 175 down range at 2700fps what could a guy achieve with the rem mag in a faster twist to stabilize the longer high BC bullets. Maybe 2850 or even 2900 fps with the same kind of accuracy was my thoughts. Plus I have had really great results with seekins precision in 6mm. (.2-.3 moa consistently) I did however manage to get Berger VLD for that caliber. I’m hoping the Hornady Eld-m bullets will not disappoint as it’s what I have available to me for the 7mm rem mag.

Update: A couple of friends from our club each sold me a 1000 primers and one pond of h100. I am very thankful for them. However the h1000 will not last me long and I would still be obligated to use h4350 if it can deliver the desired accuracy of at least .5 moa or better consistently

 

[Driftertank]

I like H1000 in 7RM, personally. I normally use it with bullets in the 160-168gr range, but my Rem 700 LR typically groups 162 ELD-M at .75-1" @ 200yd. I think it will give much better results with the 180gr bullets.

I have a friend who gets 180 Bergers going around 3k with RL26, but that stuff's nonexistent lately.

If you weren't a few states away from me, I'd offer some Retumbo or IMR7828SSC I have laying around...