7 mm SHERMAN SHORTMAG vs 7 SAUM

[elkaholic]

Rich have you tried Ramshot Magnum in your SS

I did today with one load and then had some weather issues. First try was unimpressive. I did have a good group with IMR 4831 before things went south though. I also proofed one of the velocities shot the first day with the same load and got the same reading plus 5'. The pic is deceiving. there are 2 holes in the top and only one on the bottom. The black background tore kind of weird and it looks opposite. The bottom hole is touching the top of the top 2 holes.

 

[Idaho Trecker]

That's awesome! Can't wait to see what the 180 do for you.

 

[elkaholic]

That's awesome! Can't wait to see what the 180 do for you.

I would have had some more data but a storm hit and as I was scrambling around, I dumped my loading block upside down in the dirt and mixed all the loads together. Had to go home and tear EVERYTHING down!

 

[royinidaho]

What's the velocity with the 4831 load.

I'm thinking a 168 class offering is sufficient for my needs.....

 

[elkaholic]

What's the velocity with the 4831 load.

I'm thinking a 168 class offering is sufficient for my needs.....

I did not chronograph it yet Roy and I have to get some more powder. It was a fairly mild load; I am guessing in the 2950 range? I have had to take a little rime off shooting with some life things going on......Rich

 

[elkaholic]

Finally got back out today after a few days off. I wanted to see what the 180 Hybrids would do with RL26 since the velocities with the 168's was so impressive. I loaded up 4 rounds each of 59 and 61.5 grains at a coal of 2.930". I was guessing this at about .005" off the lands? Trying to shoot groups has been very difficult as I am shooting prone off the desert sand and getting a ton of mirage in this heat! Anyway, with the first loads with the 180's and no developement, I am feeling pretty good about the possibilities. What was frustrating was the fact that the first 5 groups that I shot, the first 2 shots were touching and the third was always off a bit. It could be that this little #4 barrel is having a heating affect? Here are a couple of pics of the 2 180 loads tested.

 

[Canadian Bushman]

For just about no load development id say its impressive.

 

[elkaholic]

By the way, that 61.5 load at 3054' was NOT a primer buster. I feel I could load a little more but probably would shorten case life too much. Not bad for a case less than 2" long and a coal of less than 3"......Rich

 

[Canadian Bushman]

By the way, that 61.5 load at 3054' was NOT a primer buster. I feel I could load a little more but probably would shorten case life too much. Not bad for a case less than 2" long and a coal of less than 3"......Rich

Id say, in the pic with the dime i was shocked at how short the case was.

 

[elkaholic]

Id say, in the pic with the dime i was shocked at how short the case was.

By the way, that load did not warp the case that badly, I think it was the camera focus.......Rich

 

[gillettehunter]

That case is rather short. Very impressive performance. Looking good. Bruce

 

[Mateo]

Finally got back out today after a few days off. I wanted to see what the 180 Hybrids would do with RL26 since the velocities with the 168's was so impressive. I loaded up 4 rounds each of 59 and 61.5 grains at a coal of 2.930". I was guessing this at about .005" off the lands? Trying to shoot groups has been very difficult as I am shooting prone off the desert sand and getting a ton of mirage in this heat! Anyway, with the first loads with the 180's and no developement, I am feeling pretty good about the possibilities. What was frustrating was the fact that the first 5 groups that I shot, the first 2 shots were touching and the third was always off a bit. It could be that this little #4 barrel is having a heating affect? Here are a couple of pics of the 2 180 loads tested.
View attachment 50319

View attachment 50320

I had the same problem with the 6.5 SS, first 2 touching and the the third shot being 'far' away. Happens way too often to be coincidence.

 

[elkaholic]

I had the same problem with the 6.5 SS, first 2 touching and the the third shot being 'far' away. Happens way too often to be coincidence.

I think, in my case at least, it is the mirage issue,and/or, barrel heating where I have done my testing thus far. The crosshairs are bouncing ALL over the place! I am going to check brass to make sure it is good though.....Rich
Sometimes just changing primers will take care of what you have experienced. If your barrel/action bedding, etc. are good, it is probably a loading problem of some sort......

 

[royinidaho]

Rich,
Why would you grouse about those groups? The one shot a bit off wouldn't really register on an animal would be my thinking. Unless those groups are at 25 yards...

Your mirage and my mirage are pretty much the same. Idaho blow sand gets excessively hot as compared to the air which is the cause of mirage. Air temp can be 80 degrees and the sand will bring blisters to your hand.

My favorite drop test range is a spot where the surface of the earth in no closer than 5' below line of sight and then only for about 5'. Considering trajectory the bullet is no closer than 1000 feet from the bottom of the canyon.

However the wind there continues to kick my butt....

I'm keep'n an eye on ya. Things are looking good.