160 Accubond and H1000

[jonesse91]

I have a Ruger M77 with the tang safety in 7mm Remington Magnum. I am trying to work up a load for the 160 Accubonds but I am getting dismal velocities. With a max charge of 60 grains of IMR4350 I only attained 2800. With H1000, I worked up to 69.5 grains and got 2905. The case on that one looked the exact same as my starting charge of 66.0 grains. I am using federal GM215M primers and my gun has a 24" barrel. I don't know whether to keep working up with the H1000 with my gun or to try something else. Any help would be appreciated. Thanks.

Sean.

[Shortmagman]

Sean,

I own a Ruger Mark II in 7mm Rem mag. and I have been reloading it for almost 15 years. Here are some of the things that I have learned during that time.
1) Most of the newer manual's are very conservative with data for the 7mm Rem Mag.. I have an older Hodgdon Manual that lists 5-6 grains more of H1000 with a 160 grain bullet than any of the recent data. Following this manual I have loaded my gun with 70-72 grains of H1000 and I have gotten 3000 ft +/sec.. However this is way over the 66.0 grains that you will find on the Hodgdon web site. I feel uncomfortable doing this. I don't know why the newer manual's are so conservative but I have read that the chambers in the 7mm Rem Mag. differ greatly and that is given as the reason.

2) You can use other powders at the max load and come close to 3000 ft/sec with a 160 grains bullet. On the Hodgdon web site they show that 69.5 grains of Retumbo produced 2915 ft/sec.. Winchester's Supreme 780 gave 2948 ft/sec.. I have switched to RL-22 at just above the data from Alliant and I have gotten just short of 3000 ft/sec.. According to the Alliant web site 70 grains of RL-25 gives 3012 ft/sec from a 24 inch barrel.


You have a few choices. You can go up on the H1000 and watch for pressure signs, or you can switch to another powder and work up your loads.

[jonesse91]

As far as that 66.0 grains goes on the Hodgdon site. That is for the flat based partition. They also have data for the 162 Hornady BTSP with a max load of 70.0 grains. Would the accubond more closely follow the second of those two being as it is more similar in design to the BTSP than the flat based partition? I am just puzzled because of the amount of discrepancy on data for the 7mm if you know what I mean.

[Shortmagman]

You are correct in that their web site lists 70.0 grains for the 162 Grain BTSP. I missed that and there is a reason. The Nosler partition will produce more pressure than a cup and core bullet like the Hornady BTSP, so most manuals will give a smaller charge for it. It is because of the partition more than the flat base according to my understanding. As stated I have used 70-72 grains without pressure signs in my Ruger shooting the 160 grain Accubond. My max was 72.0 grains and this load gave me 3025 ft/sec..I know what you mean when you say that the discrepancy in data is sometime puzzling.

The Accubond is built more like the cup and core bullet but because it is bonded it acts more like the partition when it come to shooting animals. If you work up slowly and watch for pressure signs you should not have trouble with increasing your charge above the 69.5 grains that you are now using.

[freebird63]

For what its worth, many years ago when I still lived on the Oregon coast I had the exact same rifle, should have never gotten rid of it as it was the best shooting gun to date I have ever owned. But my best friends dad reloaded for me, I just bought the components for him. I was shooting 162gr hornday BTSP with CCI mag primers and IMR 4831. His load was 67gr of IMR 4831. Now we didn't have a chrono back then and I never had any sticky bolt or lose primer pockets. But I see in todays loading manuals that is an excessive load. All I ever hunted were little blacktails and they were DRT. Good luck
The gun I shoot today is a 280AI and had good luck with 162gr A-Max with H1000. Have since switched to 160gr accubonds but have yet to shoot them. Good luck and keep us up to date on your load.

[MachV]

My old tang safty M77 in 7 Mag has taught me more about reloading in the last 30 years than all the other rounds combined..... And I'm still confused at times
two things its really taught me is pay attention to the resizeing die! If I resize all the way to the shelholder on either of the two resizeing dies I have the case is toast in three round MAX. If I just bumb the shoulder back a very little or just neck size I can get 5+ reloadings with no problems.
The second thing its taught me is that H1000 and R22 sometimes works depending on the lot!!!!!!!!!! Had an old lot of R22 years ago that we where 7 grains over book on with no preasure signs and it shot great with this load. The next lot I got Blew primers a grain under book. The tell me the new lots of H1000 will do the same thing useing old info.
The other thing is its a lot fussy about ammo. It dont like accubonds or most polimar tips for that matter but prefers 160 Partisions and will shoot MOA out past 500 with numerous powders including H870,IMR7828,H4831sc,H4350,R22 & R25

[jonesse91]

Haha. I must say I've had a similar experience with my gun. I couldn't get the darn thing to hold under 1.5" for my life until I tried remington green box. 150 grain core lokt's will one hole all day. Only problem is that the velocity is an acclaimed 3110. Well, its really only pushing 2920. However, the accubond has shown some promise here at first but if it doesn't work out I might try the 162 BTSP.