7mm 08 Sierra 100gr HP LOAD?

[Cooper]

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I bought some Sierra 100gr hollow point from the local. They were pretty cheap $42 per 100. Just thinking of using them as a varmint load. Decided to at 42gr of AR2208 which is where I am at with HORNADY SST AND INTERLOCKS both 139gr.

They shoot fine and the point of impact is very similar to my other loads. Decided the run the magneto speed over them on the weekend and to my surprise were only doing 2680fps.? I was expecting closer to 3000fps. I tried my other loads which usually do 2740fps and got 2720fps is was only 8 or 9 degrees at best.

I guess the similar velocity explains the similar point of impact. But I was still thinking the lighter bullet with the same powder charge should be going a bit quicker. Also see Sierra load data in picture. Varget is AR2208. I am a fair way down from book velocity. Rifle is a Tikka 7mm08 lite 22inch barrel.

Thinking AR2206H might give some more velocity with the lighter bullets?

[happyhunter]

42 grains is pretty light. You got plenty of room to move with AR2208 from that, but I'm guessing you are on the money with AR2206H working better with light projjies in the 22" barrel. Give it a crack and see what happens.

[bladeracer]

But I was still thinking the lighter bullet with the same powder charge should be going a bit quicker. Also see Sierra load data in picture.

Did you seat it to the depth listed or the same length as the 139's?

[Cooper]

But I was still thinking the lighter bullet with the same powder charge should be going a bit quicker. Also see Sierra load data in picture.

Did you seat it to the depth listed or the same length as the 139's?

Seated it to the depth listed. But I did measure from the base to the tip.
The SST would be taking up heaps more case capacity. Causing higher pressure?

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[Gwion]

You won't get same POI as other loads if you get higher velocity. Can't have it both ways.

A heavier pill actually used less powder because it develops higher pressure as it takes more to move it down the barrel. I would do a few test loads in 0.5gn increments up to about 44.5 with your current powder. That's 15 bullets gone if you do 3 shot groups 42.5 up to 44.5gn. It will give you a basic idea of accuracy. Pick the one with best accuracy for the 3 shots, load 10 of them and shoot a test group of 5. If it's all good, use the other 5 to set your scope.

If you can't be bothered with that, just go with it as is and use them on lighter game. It will save you mucking around with the scope too much, which is an advantage of having interchangeable loads shooting to the same POI.

[duncan61]

I load the exact same bullet in my 7mm Rem Mag for 3300fps over 56gr of 2208 I have a Sendero with a 26 inch fluted S/S barrel.I find it an excellent bullet for head shooting Kangaroos at long range in the daytime.I have not shot a fox yet but will work on it.The POI is totally different from the 168 M/K on 64gr of 2213sc.If your POI is similar I would probably be happy rather than going for more velocity and expense.The game will not tell the difference

[Wobble]

If your POI is similar I would probably be happy rather than going for more velocity and expense.The game will not tell the difference

Totally agree.

2 different loads with same POI sounds perfect to me.