Choosing powders for 458 Lott from Quickload/Gordons Reloading Data?

[Nhoro]

Thanks shootist43 -I only have a kitchen scale so my case capacity is between 108 gr and 114 gr(accuracy of the scale). To add to that, the Pergrine is 515 gr and is seated 18.5 mm seating depth. Bullet length is 38.3 mm. So there is a further change in parameters/Available case volumes. Anyway I am going across town tomorrow to load a couple more rounds and chrono on the weekend. Your data agrees with my observations and I feel more comfortable pushing the powder up to maybe 72 gr IMR. I have a camp at the end of the month and will be happy with that. Then I may need to get a tin of VV 530 and ask my friend to keep it for me. That looks like the better powder of what I can get.

I am completely comfortable with a solid 2150 fps with the 515 gr Peregrines. The 2200 is just a little breathing space above where I am comfortable.

 

[Shootist43]

Sorry I can't be of more help. QuickLoad does not have a 515 gr. Peregrine in its' data bank. Only 500 Gr. in "variants" VRG1, VRG2 and VRG3. Good luck finding something that works for you.

 

[Nhoro]

Thanks Shootist. Apparently, they have changed the 500 gr to 515 gr, VRG2. But this thread was great-it helped me get my head around the loads/pressures and powder choices. I am happy now.

 

[Desperatezulu]

Adding my 2c late in the piece - the Peregrine reloading data typically uses SA powders (Somchem) because that's what was available in SA until the last year or so. Most of that reloading data was derived a few years back.

In terms of load density, 100-105% is ideal for consistency and helps a bit in stopping your bullet 'setting back' under recoil if you haven't crimped it. I would suggest caution if using flake/spherical powders like S321 and loading over 100% case fill. Storing this ammo for extended periods at high temps sounds like a recipe for clumping/caking, and not in line with your 100% reliability requirement.
So if possible use a coarser, extruded granule powder if if going for a compressed load.

I think you'll be very happy with the VV powder if you're used to Somchem

 

[Nhoro]

Adding my 2c late in the piece - the Peregrine reloading data typically uses SA powders (Somchem) because that's what was available in SA until the last year or so. Most of that reloading data was derived a few years back.

In terms of load density, 100-105% is ideal for consistency and helps a bit in stopping your bullet 'setting back' under recoil if you haven't crimped it. I would suggest caution if using flake/spherical powders like S321 and loading over 100% case fill. Storing this ammo for extended periods at high temps sounds like a recipe for clumping/caking, and not in line with your 100% reliability requirement.
So if possible use a coarser, extruded granule powder if if going for a compressed load.

I think you'll be very happy with the VV powder if you're used to Somchem

Thanks-Just got back from reloading a test round. Sat with Chris (very experienced reloader) and chatted it through with him. Quick summary Vihtavuori powder is reliably available- imported from SA. Then we worked through the options -VV 130,530,540 and 550 on his quickload. 550 gives best velocity for pressure. He had just loaded 550 gr woodleighs with that powder to about 2170 fps with 82 gr of powder. So we are going with that on Saturday. A bit faster than I first planned, predicted 2225 fps and far more grains of powder but the 550 seem to be generally lower pressure vs velocity it gives than other powders. Have a look below at the load info.

 

[Nhoro]

Oh I forgot to mention, this will be my carry load- so protection on walks and hopefully some problem animal control so that I can finish of my license.

 

[Nhoro]

Complete about turn on the powder. I have done a whole lot of playing with loads and powders. It is quite interesting to be able to play with powders and get some kind of indication of performance.The program suggests Vihtavuori N530 and N133 are best of the VV line but best of all was S321 ie most velocity without dangerous pressures.So Finally tested a load on Saturday Somchem S321 powder- 82 grains resulted in 2345 fps with 515 gr copper monolithic. Recoil was stout but I am alive and no bruises.So I will be loading that down a bit- probably 79 gr for an uncompressed load. I had no pressure signs but 19 deg C is pretty different to the Valley. Guys at the range said they have had a sticky bolt with that load.

 

[Alistair]

The things are care about with the Gordons tool are:

- Pressure
- Velocity
- % Powder Burn
- % Case fill
- Weight of charge required
- Non-performance factors.

The first thing I look at is velocity and pressure. High velocity, low pressure is best, obviously. If I have a specific velocity in mind, anything that won't do that with (dangerous pressure - 15+%) can be eliminated.

The first step gives a shortlist. If this list is short, there's your options and I'd buy based on what I an source reliably.

If the list is long, we move onto powder burn and case fill. A good candidate powder should allow 95%+ burn in your barrel length and ideally a case fill between 90% and 100%. Mildly compressed is also ok, but wouldn't be my preference.

You should now have a couple of powder options. Of these and if all can be sourced, I tend to pick the lowest charge weight. This in theory will give slightly less recoil and also costs less if you're buying by the lb.

The final factors are the extraneous factors; price, flame temperature (double vs single base powder) and also powder handling. These won't make it shoot better, but will make your life easier.

With some non-precision guns where I shoot large volumes of rounds (lever action shoots, running boar, McQueens) I want to throw charges and not weigh every time, so short kernel lengths or even better, fine ball powders get the nod from a throw consistency standpoint. Price is self explanatory, whilst I find that flame temperature correlates closely to barrel wear, especially in string shooting in overbore cases.

 

[Nhoro]

Thanks Alistair, that is exactly where my thinking was going.. And what are your thoughts on the accuracy of Gordons ? Compared to Quickload, it look like it predicts higher pressures and higher velocities than Quickload.

I am guessing all programs have a built in safety-predict higher pressure so that guys dont push the boundaries but Gordons is predicting 70 % overpressure and about 175 fps more than chronograph. And this load showed no obvious signs of over pressure.

 

[Alistair]

Check your actual case capacities.

Gordon is pretty conservative as standard, but plug in the actual case volume instead of the defaults and it's pretty good.

I was within 50fps for every load I worked up with it across 4 calibres. No idea on the actual pressures, but I'm still here and my rifles are in one piece, so meh.

 

[Arthur Morta]

Thanks-Just got back from reloading a test round. Sat with Chris (very experienced reloader) and chatted it through with him. Quick summary Vihtavuori powder is reliably available- imported from SA. Then we worked through the options -VV 130,530,540 and 550 on his quickload. 550 gives best velocity for pressure. He had just loaded 550 gr woodleighs with that powder to about 2170 fps with 82 gr of powder. So we are going with that on Saturday. A bit faster than I first planned, predicted 2225 fps and far more grains of powder but the 550 seem to be generally lower pressure vs velocity it gives than other powders. Have a look below at the load info.

Hi Nhoro,
Did you shoot and would you be so kind as to share the results you got when using N550 with the Peregrine's?

 

[Nhoro]

550 was a bit slow with the 515 gr peregrines. I just had one load and it was far off. It works with Woodleigh conventional solids. I think the copper monolithic with driving bands needs a faster powder- I suspect it accelerates quicker. I got results with vv130 and 133 as I recall and vv 530 is the best with peregrines. I will have to look on my computer at my notes and then I will post that.

 

[Kalaharibushbaby]

Complete about turn on the powder. I have done a whole lot of playing with loads and powders. It is quite interesting to be able to play with powders and get some kind of indication of performance.The program suggests Vihtavuori N530 and N133 are best of the VV line but best of all was S321 ie most velocity without dangerous pressures.So Finally tested a load on Saturday Somchem S321 powder- 82 grains resulted in 2345 fps with 515 gr copper monolithic. Recoil was stout but I am alive and no bruises.So I will be loading that down a bit- probably 79 gr for an uncompressed load. I had no pressure signs but 19 deg C is pretty different to the Valley. Guys at the range said they have had a sticky bolt with that load.

Have you lately loaded the Riflex green cap (S321) in the lott ?
I bought a bunch of this for the 223/AR .
I use the Peregrine VRG3 300GR on my 375HH with very good results on dangerous game. Have to start loading my lott.
Will defenitely use Peregrine on the lott.

 

[hoytcanon]

Big Bore rifles are not paper punchers... I don't worry about target velocity or target pressure, I worry about the "TARGET."
Just choose an appropriate powder for your bullet and work up, while you monitor the accuracy carefully.
My Lott load in my M77 Mark II RSM is 85 grains of A2520 with Hornady 500 grain DGX/DGS... that is where I hit the sweet spot for accuracy.