Heavily compressed loads

[DLH_]

Dear all,
Following bullet seating this afternoon I have a few concerns about heavily compressed loads. After charging sixteen 243 cases in preparation for a ladder test at the start of next week with a range of 46-48.5gr of H4831SC; I ran into slight problems with seating. Upon attempting to seat the 87gr V-Max's, I had to adjust the Wilson micrometer seater very slightly (3 thou with the max charge) to maintain my desired seating depth. I am going to measure them again later on to see if they have changed at all due to the heavy compression and only 0.0015 neck tension. Will I experience any pressure spikes as a result? Do I have any reason to be worried?

Thanks,
Josh

 

[Sniper338]

Considering the sierra manuel says 42-45.3 max, Id say you should be concerned and re evaluate your loading data. sounds like your gonna blow up yourself.

 

[Sniper338]

plus for best accuracy you wanna load closest to the time your gonna shoot... the night before or day before is better to keep more consistant neck tension.

 

[Sniper338]

and if your powder charge is so compressed it pushes the bullet back out, common sence should tell you somethings not right.

 

[geraldgee]

I agree with the comments above...you are 7% over max.

Be careful.

Gerald

 

[DLH_]

The Hodgdon online load data states a maximum charge of 48.0gr with a 90gr bullet. I also saw the Sierra data and loaded a few foulers according to their data working up.

Thanks
Josh

 

[dkhunt14]

A lot depends on bearing surface and bullet diameter. Fat bullets cause higher pressure and so does longer bearing. Usually it is not a good idea to use one companies load data for another ones bullet. It isn't just the weight that causes pressure. Matt

 

[DLH_]

I think I'll just pull them and start from scratch. However, my current load for the 87gr V-Max is 44gr of IMR 4350. According to the Sierra manual, 1.8grs over max charge. I have no pressure signs, brass is on its 9th firing, no stiff bolt lift, no primer flattening, no cratering. Slight ejector mark but this is always present in the rifle, even with starting loads. All three of my Borden action rifles show the same trend.

 

[smoooth]

There are also huge variations between loads from company to company, year to year, and lot to lot. My (old data) .243 load is way over (new data) max listed but has NO pressure signs IN MY RIFLE. Common sense goes a long way, start low, work up, STOP when you see pressure indicators.

Also, a drop tube would help settle that powder, as would a little light tapping on the case.

Best of luck!

 

[DLH_]

I do expect a few signs with the top two charges but it will be worked up to slowly.

Thank you all
Josh

 

[jimbires]

I had a compressed load that would push the bullet back out . I would reseat the bullets the next day and they stayed where I wanted after that . like was mentioned above a drop tube funnel sure helps with high case fill loads .

 

[DLH_]

I use the electric tooth brush method to settle powder. By using this method, I can individually weigh each charge.

Thanks
Josh

 

[Webster]

Dear all,
Following bullet seating this afternoon I have a few concerns about heavily compressed loads. After charging sixteen 243 cases in preparation for a ladder test at the start of next week with a range of 46-48.5gr of H4831SC; I ran into slight problems with seating. Upon attempting to seat the 87gr V-Max's, I had to adjust the Wilson micrometer seater very slightly (3 thou with the max charge) to maintain my desired seating depth. I am going to measure them again later on to see if they have changed at all due to the heavy compression and only 0.0015 neck tension. Will I experience any pressure spikes as a result? Do I have any reason to be worried?

Thanks,
Josh

Why do you think you need to push the limits. Go for a lower charge and accuracy. If it's a hunting rifle a deer doesn't know the difference between a 3000 and a 3200 fps bullet.

 

[savagedasher]

Long drop tube and a slow pour

 

[Zero333]

At 2.710" coal, 48.5 gr of H-4831sc should not be a very compressed load.

If you're loading shorter than 2.710" you will be maxing out near 48 gr.

This is if you're using Winchester brass... I found Lapua brass reaches pressure signs at a lower charge weight.

I've shot up to 48.2 gr of H-4831sc under a 90 gr Berger BT in Winchester brass. BUT I had them loaded at 2.810" coal which left me more room in the boiler and allowed me to 48.2 gr with out any issues. Best accuracy was at 47.2 gr anyways.

Shorter COAL = less case capacity = reach max pressure with less powder.

 

[Sniper338]

The Hodgdon online load data states a maximum charge of 48.0gr with a 90gr bullet. I also saw the Sierra data and loaded a few foulers according to their data working up.

Thanks
Josh

just work up to it... dont start at max... even just 1 shot of lower ranges to watch for pressure is fine... just test safely is all im saying

 

[Metal God]

Is H4831 the same as H4831sc ? The website has H4831 listed but not H4831sc . I don't use the powder but always thought even if it's the same powder when they cut the sticks in half it acts different then it's original form . Burn rate and ignition characteristics change when they change long stick into shorter stick powder . It fits in the case different so I'd expect at minimum the ignition and start pressure would be different .

Now this is me just thinking out loud here but if they are actually different powders , that would be me first thoughts . I'd be hesitant to use H4831 data in place of H4831sc

 

[DLH_]

Thank you all. I'm using Sako brass. Can't comment on COAL, I'm measuring from the ogive with a stoney point bush. Despite the V-Max being a varmint/hunting bullet, the intended purpose for me is long range steel shooting. With the 1/10 Twist, the 87gr V-Max is the higest BC bullet that I can stabilise. The only bullet that I've not tired yet is the 90gr Scenar- In the 85-100gr range. If I do not run into pressure signs, I will shoot them and try a different powder.

 

[Zero333]

Is H4831 the same as H4831sc ? The website has H4831 listed but not H4831sc . I don't use the powder but always thought even if it's the same powder when they cut the sticks in half it acts different then it's original form . Burn rate and ignition characteristics change when they change long stick into shorter stick powder . It fits in the case different so I'd expect at minimum the ignition and start pressure would be different .

Now this is me just thinking out loud here but if they are actually different powders , that would be me first thoughts . I'd be hesitant to use H4831 data in place of H4831sc

H-4831 and H-4831sc is EXACTLY the same.
I've shot both versions for many years, interchanging with out going out of tune nor getting different velocities.

I use the SC version when the standard version fills the case too much. I don't like very heavily compressed loads.

 

[Zero333]

I think I'll just pull them and start from scratch. However, my current load for the 87gr V-Max is 44gr of IMR 4350. According to the Sierra manual, 1.8grs over max charge. I have no pressure signs, brass is on its 9th firing, no stiff bolt lift, no primer flattening, no cratering. Slight ejector mark but this is always present in the rifle, even with starting loads. All three of my Borden action rifles show the same trend.

I don't think you really need to pull the cartridges apart since your starting charge is low enough at 46 gr to safely give it a shot.

Go and shoot them from 46 gr and up, while watching for any pressure signs.
Sometimes I've had loads that showed pressure with one type of primer and not another.
You just never know till you try.

If for whatever reason the 46 gr load has any signs of pressure, I'm sure they will be very slight and give you a safe heads up as to what's happening.