Load Development 7mm Rem Mag/175 Berger El

[jdmecomber]

I made a home made annealing machine. If you look on you tube there are bunch of videos on them. Its basic but works! I didn't want to spend the money on bench source. I probably have 50 dollars in mine and 2hrs of my time.

Nice

 

[jdmecomber]

Es is still not there but we shot 3 good groups today.

68 grains of powder hit 3010 fps and had a .19 ish moa

67.5 grains of powder was about 50 fps slower and .20 ish moa

65.4 grains of powder was about 2830 fps and .20 ish moa

 

[Capt RB]

Fed 215's are really soft cups. CCI's are harder. They can also be a better primer for sd's I see best results for sd's with 91/2m's but they are smaller diameter so they don't last long after a couple hot loads because of pocket expansion.

 

[jdmecomber]

Fed 215's are really soft cups. CCI's are harder. They can also be a better primer for sd's I see best results for sd's with 91/2m's but they are smaller diameter so they don't last long after a couple hot loads because of pocket expansion.

This is still new brass so I think once we get the once fired brass in the mix it should improve.

 

[jdmecomber]

It appears retumbo isn't going be ideal for hitting that higher velocity node. We are getting 2919 fps with 68.4 grains. It's winter here. The shop is about 52 degrees. If we go up to 69 grains, I wouldn't feel good about a real hot summer day. The risk of over pressure is there. We did shoot a really good 4 shot group with the retumbo. Es wasn't too bad. I bet it was .20 moa.

We need to shoot the Reloader 26 again. We have a flat spot at around 2950 fps. We shot a decent 4 shot group with a 12 Es, so I think we found a winner. We are going to get H1000 up to the node just for fun and see what it does.

 

[jdmecomber]

Well
112 rounds in and it appears the barrel has settled.

We settled on a node in the 2940's. It has produced three groups now with 7,12 and 15 ES. This gun with Reloader 26 hasn't produced a group over .75 moa with 3.5 grains of powder around 190 fps in total spread. I think once I get prone these groups will get better. We have multiple groups under .20 moa.

We tried some other powders around the same node of 2940 and it was a failure. The other powders were very unstable in the same node. H1000 and Retumbo were used.

Imr 7828 SSC had around an moa in group size and about a 15 ES with new brass. I think this could really improve with fireformed brass and some lands movement, but this is a hunting rifle. The customer should be happy.

Attached Files:

 

[8andbait]

I always had good luck with retumbo and 175's usually around 70-71 gr and about 3000-3030 depending on barrel length.

No arguing the rl26 results you got though.