300wsm reloading quesrions

[eastkoots]

I have a sako finnlight in 300wsm. Id like to develop a 175 lrx load for it. I loaded up a few rounds with h4350 and ladder tested from 63gr all the way to 65gr and only got 2470fps. Im using magnum primers.

What could possibly be causing the load to shoot this slow? Max load for this is 67 gr according to barnes.

Any insight would be greatly appreciated.

 

[SDHNTR]

What’s your powder measuring process?

 

[eastkoots]

What’s your powder measuring process?

Frankford intelli-dropper. Calibrated using weights.

 

[turbobrick]

If Barnes says 67 is max, I'd keep going, those last couple grains could make a big difference.

 

[01Foreman400]

If Barnes says 67 is max, I'd keep going, those last couple grains could make a big difference.

Their old load data is different than the new data on some cartridges. New is more conservative. For example on the 257 Weatherby Mag and H1000. I started getting pressure signs at 74.5 grains with a heavy bolt lift. I brought it down 74.2 grains. With the new data at max I was getting a touch over 3,400 FPS. The old data I got up to 3,600.

 

[turbobrick]

Something isn't adding up, I ran the numbers through Gordon's reloading tool, and it shows 65gr being overpressure, and 67 being way, way overpressure.

My only Barnes manual I have in print doesn't have the 175lrx, and does not have data for H4350 on either weight projectile above or below.

Specifically, what magnum primer are you using?

 

[.270]

I would double check your charge weights, that velocity seems a bit low. Its not apple to apples but my 325 wsm with 200gr and 62.5 H4350 is going 2740 in a 22" barrel. Did switch to RL-17 and gained more velocity.

 

[wytx]

I'm pushing 65 gr of 4350 with my 165 gr bonded bullets in my 300wsm. Spouse loads 64 gr for his 180 ABs.
Your numbers aren't adding up.
We both have over 3,000 fps.

 

[SDHNTR]

Frankford intelli-dropper. Calibrated using weights.

Double checked on a balance beam?

 

[eastkoots]

Double checked on a balance beam?

No, but looks like I definitely should.

 

[SDHNTR]

No, but looks like I definitely should.

Yep. I bet your calibration is off. IMO, any electronic scale needs to be verified by a manual balance beam, every session.

 

[BCsteve]

I load 175gr LRX with 64.5gr of H4350 in my Winchester M70 with a 24" barrel. Chronoed velocity is 2970 fps. Something doesn't add up.

 

[eastkoots]

Something isn't adding up, I ran the numbers through Gordon's reloading tool, and it shows 65gr being overpressure, and 67 being way, way overpressure.

My only Barnes manual I have in print doesn't have the 175lrx, and does not have data for H4350 on either weight projectile above or below.

Specifically, what magnum primer are you using?

Youre right. I need to double check my powder on a balance beam. And ladder test from there. I think my frankford might be grossly undercharging. I am using white river magnum (all we can get in canada right now). I am getting 0 signs of pressure at "65" so im thinking my powder machine is funky.

 

[HandgunHTR]

What chronograph are you using?

That may be the culprit as well.

 

[eastkoots]

What chronograph are you using?

That may be the culprit as well.

Garmin. It was bang on with factory ammo and other rifles that day.

 

[punklife505]

My load with 175 LRX is moving at 3150ish fps with 64.4 grains H4350...playing with the seating depth to tighten it up but its huntable as is.

 

[eastkoots]

View attachment 903149My load with 175 LRX is moving at 3150ish fps with 64.4 grains H4350...playing with the seating depth to tighten it up but its huntable as is.

Awesome!

 

[turbobrick]

Youre right. I need to double check my powder on a balance beam. And ladder test from there. I think my frankford might be grossly undercharging. I am using white river magnum (all we can get in canada right now). I am getting 0 signs of pressure at "65" so im thinking my powder machine is funky.

I had an older electronic scale/dispenser, and started getting weird results out of it. Was looking through the manual, and it said allowing the machine to be in freezing conditions would basically ruin it. I’d stored it in my garage during a move, and it definitely saw freezing conditions. It gave consistently low readings, read 29gr but it was spitting out 32. This was a long time ago, but made an impression on me for sure.

 

[TaperPin]

I have a sako finnlight in 300wsm. Id like to develop a 175 lrx load for it. I loaded up a few rounds with h4350 and ladder tested from 63gr all the way to 65gr and only got 2470fps. Im using magnum primers.

What could possibly be causing the load to shoot this slow? Max load for this is 67 gr according to barnes.

Any insight would be greatly appreciated.

That must have been a really strange feeling when the chrono kicked back that velocity! Hopefully it’s an easy fix.

In the back of my mind it’s automatic to think “what if that doesn’t fix it?” Some Barnes data is a little slow, maybe 100 fps in some guns. I’ve heard of a bad lot of powder being a few hundred fps slow, but that’s not even close. I had a rifle with a tight bore, slow barrel that was never closer than about 100 fps of a max load before it was over pressure. It would take all those things together, and then some.

 

[IDElkmagnet]

Something is wrong. My closest load is 64.5gr h4350 with a 178 absolute hammer, wlrm primer. Out of a 24" of proof barrel it's going 3035 fps on my garmin.
In my experience the white river mag primers are actually hotter than wlrm.