Should I use magnum primers with IMR 7977

ltrmc02

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Nov 23, 2011
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I just picked up some IMR 7977 to try in a .280 Remington. For now I plan on shooting 154gr SST and 162gr Amax pills. What do you guys think I should start with standard or magnum primers?
 

Shortmagman

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If you check the Hodgdon web site they used Remington 9 1/2 large rifle primers and WLR for their 280 Rem loads. When they moved up to the 7mm Rem Mag or the 270 WSM they used WLRM primers.

I have loaded and shot this powder out of my 270 Winchester and my 270 WSM. With the standard 270 Win I used WLR primers with the 270 Mag I used WLRM primers.

I think the standard large rifle primers should work well in your 280 Rem.
 

ntg

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Shortmag,

I know this is a little old, but any more info on the 270win loads. I'm tempted to try this powder in my 270win.

Thanks.
 

bigedp51

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The latest Hodgdon's Reloading Annual Manual has a article on loading the three new powders. And shows loads for the .270 Win with CCI 200 primers.

The author states that Hodgdon's recommends standard primers with standard cases and magnum primers with magnum primers.

Check out how the various did below.


Primers - Large Rifle Primer Study

A Match Primer Study in the 30-06 Cartridge


By Germán A. Salazar
This article was originally published in the September, 2008 issue of Precision Shooting

The Rifleman's Journal: Primers - Large Rifle Primer Study
 

Shortmagman

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ntg,

I am loading IMR-7977 in both my 270 WSM and my 7mm Rem Mag with very good results. I have not loaded enough in my 270 Win to offer any advise, however I just received the Oct edition of Rifle's Handloader mag and found a article where IMR-7977 was used. This article was written by John Barsness and he used IMR-7977 in a 270 Win. . He was able to get 2816 ft/sec. using 150 grain Sp.out of a 22 inch barreled Winchester Model 70. His load was 60 grains of IMR-7977, Winchester cases, WLR primers loaded to a COL of 3.345. His accuracy was just over an inch for 5 shot groups.

I am going to try this load, working up of course in my 24 inch barreled 270 Win.. I have been very pleased with this powder in the two calibers that I have tried so far and I think it should work well in a 270 Win.
 

PGJPJ

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I'm not sure. I've read some guys using RL26 in 280 ai cases having better luck with the magnum primers. Some theorize the really slow powders do better with mag primers. At least in the 30-06 family case.

7977 may be about there, so it might be worth some experimenting.

My 270 win did just fine with standard primers and RL22, so I don't have any experience to offer.
 

Shortmagman

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Ntg,

I just got back from the range! One of the loads that I tried in my Vanguard 270 Win was 150 grains Hornady SST's and IMR-7977. I did not chronograph any of my loads but I was very pleased with the accuracy that I was able to achieve using 58.0 grains of IMR-7977 in Winchester case and WLR primers. I started at 57.0 grains and worked up toward 60 grains as a max. My 57.0 load was ok and the 59.0 load was fair, just take a look at what my 58 grains load looks like.
 

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Shortmagman

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I went to the range yesterday and took my CED with me, along with five different rifles. I had a great time and the weather was almost perfect in the high 70's with low humidity and plenty of sun.

Ntg- I shot my 270 Win with 150 SST's and 58.0 grains of IMR-7977 average velocity 2823/ft/sec. 58 is two grains below the max., so I think it would be easy to get 2900 + with this powder and a 150 grains bullet.

7mm Rem mag. 3033 ft/sec with Nosler LR Accubond and the max load of 70.9 grains of IMR-7977. Also good accuracy with one 3 shot group of .37 inches at 100.


270 WSM was the star of the day. 150 VLD, 66.0 grains of IMR-7977 in Norma cases and Fed 215 primes. 3143/ft/sec and with this load I shot one three shot group of .14 inches. I quit with this group because I knew if I shot more I would only get much worse.
 

Mossy49

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Short mag , quick question what grain ABLR bullet are you shooting with your 7mm. I'm curious cause I'm shooting a 175 ABLR out of mine and it shoots great withRL22. But I'm thinking it might be to temperature sensitive up here in Alaska. And it's nice to have another option of powder on hand here too. Thanks.
 

tony m

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elk valley BC
I just picked up some IMR 7977 to try in a .280 Remington. For now I plan on shooting 154gr SST and 162gr Amax pills. What do you guys think I should start with standard or magnum primers?
I cannot see what it hurts to use hotter primers for everything.I have gone from using standard to magnum primers on all my centerfire rifles.
 

Shortmagman

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Mossy49

I am shooting the 150 grains ABLR out of my 7 mm Rem mag. I don't think I could get over 3000 ft/sec with the 175. So far I like the IMR-7977 powder in all three guns that I have shot it in. I am getting good accuracy and good velocity without going above the book loads. The only thing that I wish was better is the extreme spread. My extreme spread is around 30 ft/sec and this would not be that good at very long range.
 
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