7 saum unexpected velocity

[XTRTITAN]

I have a 7 saum with a 26" critirion on a savage pta. I am getting 3150 fps shooting berger 180 hibrids over 54.5 grains of h4350. The combo shoots .5 at 100 but is showing lots of vertical at distance. I am using cci 250 primers and wondering if it would be better to used standerd primers or would it be better to reduce the charge until i get the 2950-3000 fps range that everybody seems to be using. Any help is greatly appreciated as range time is limited. Thanks in advance

[elkaholic]

Originally Posted by XTRTITAN

I have a 7 saum with a 26" critirion on a savage pta. I am getting 3150 fps shooting berger 180 hibrids over 54.5 grains of h4350. The combo shoots .5 at 100 but is showing lots of vertical at distance. I am using cci 250 primers and wondering if it would be better to used standerd primers or would it be better to reduce the charge until i get the 2950-3000 fps range that everybody seems to be using. Any help is greatly appreciated as range time is limited. Thanks in advance

That sounds AWFULLY high! Are you sure your chrono is giving you correct velocity?......Rich

[XTRTITAN]

I am using the trajectory for velocity. It takes 21.5 moa to reach target at 1035 yds with a 100 yd zero. Havent had a chance to chrony it yet but with the jbm program this gives me a velocity around 3150.
I cant believe i am getting that trajectory with a 26 inch tube. I dont think the velocity is stable because of the vertical i am seeing. I will get the chrony out and double check the velocity asap.

[elkaholic]

Originally Posted by XTRTITAN

I am using the trajectory for velocity. It takes 21.5 moa to reach target at 1035 yds with a 100 yd zero. Havent had a chance to chrony it yet but with the jbm program this gives me a velocity around 3150.
I cant believe i am getting that trajectory with a 26 inch tube. I dont think the velocity is stable because of the vertical i am seeing. I will get the chrony out and double check the velocity asap.

I think that explains it. That velocity sounds near imossible to me! Something is likely wrong with data input. Let us know what the chrono reads.......Rich

[trueblue]

Originally Posted by elkaholic

I think that explains it. That velocity sounds near imossible to me! Something is likely wrong with data input. Let us know what the chrono reads.......Rich

Agreed.cannot get that kind of velocity out of a 7SAUM w/the 180's. and a 26" barrel.
You are into 7-300WM territory now.

[liltank]

You need to find out what your extreme spread is also. Sounds to me if you are getting a big vertical dispersion that you have a big ES. Changing your primer to a large rifle might help to calm that down some. It will effect your velocity too. Pressures should be lower also. You'll definitely need to use a chrony to see what your numbers are.

[jabey9210]

Maybe the actual bc of the bullet is off a bit cause you can change the bc on jbm to get your correct trajectory also. I shoot a 7mm Wsm and get exactly 3000 fps out of a 27" tube with 180 berger vld's according to the chrono and with that my trajectory is right on with jbm I thought they were pretty hot loads but I'm on my 6th reload on this brass so they must not be too bad. But out of my 243 if I go with the chrono and jbm they are off so since I know the chrono is pretty accurate I change the bc and get the correct trajectory if I changed the fps it says I'm shooting about 200 fps faster than I actually am so either way as long as your trajectory is right on the numbers in jbm are just that and really don't matter as long as the trajectory lines up!!! I also agree with checking your extreme spread if you're having vertical issues!!