So, I Was In The Loading Room Today...

[tarbe]

So I was in the loading room tonight, putting together some test loads in the 450/400 (400gr A-Frame) and also some plinkers for the 458 Lott (500gr TSX).

It is pretty amazing how different the charge weights were in these two cartridges, using different powders geared to the expansion ratios and pressure limitations of these two very different cartridges.

The 450/400 400gr loads were using 94 grains of powder for 2,250 fps while the 458 Lott 500gr loads were using 68 grains of powder for 2,100 fps.

As you might suspect, their was a pretty significant difference in burning rate between these two powders!

 

[Pheroze]

The belted magnum variants seem to also make efficient use of powder. If memory serves me, the 416 RM uses less powder than Rigby to achieve the same velocity.

 

[tarbe]

The belted magnum variants seem to also make efficient use of powder. If memory serves me, the 416 RM uses less powder than Rigby to achieve the same velocity.

Yes,a fair bit less powder.

Between the expansion ratio (case capacity vs bore capacity) and pressure differences, the Remington uses less, of a faster powder, to achieve the same velocity.

 

[Pheroze]

But, I am quite amazed that the 450/400 uses so much powder. Interesting

 

[sestoppelman]

The belted magnum variants seem to also make efficient use of powder. If memory serves me, the 416 RM uses less powder than Rigby to achieve the same velocity.

Of course, smaller case. Compare the .308 to the '06, same thing. Not magic. The belt has nothing do to with it, its simply there as a headspace method, nothing else.

 

[Pheroze]

Of course, smaller case. Compare the .308 to the '06, same thing. Not magic. The belt has nothing do to with it, its simply there as a headspace method, nothing else.

I know it's not the belt. It's just the overall design. I just hadn't really turned my mind to its efficiency. The 400 H&H will also send that same bullet at 200 fps faster with 20 grains less than the 450/400. That's something more than 308 and 3006 comparison I think.

People always mention the belt, good/bad blah blah, but not much is said about the efficiency. Just interesting is all.

 

[sestoppelman]

I know little of the .400 H&H other than what it is, or what it will do. I would be skeptical that it can do as stated. But if so, the only reason would be loading it to max with a smaller capacity, than the other, and not loading IT to max. There aint no free lunch. If capacities are nearly the same, loaded to their full potential, velocities will be about the same. The .308-'06 comparison is valid because with any given bullet weight the .30-06 can drive it about 200 fps faster, again with max loads for both. In factory guise one might say the .308 is more efficient as it comes close to factory '06, but loaded to full pressure and ability, no. But the magnums, not sure what you mean by efficient. Most are anything but. Efficient rounds are the ones that do the most with the least, and that doesn't usually apply to magnum rounds. Again, the belt lends nothing to the equation, its simply a means to headspace, no more no less. And yes it is interesting.

 

[Pheroze]

In case you are interested I received these from Cutting Edge Bullets - Max loads shown. Use at your own risk. For 400 gr Cutting Edge Safari Solid

Not sure why its sideways.

 

[sestoppelman]

Its an interesting round. I thought about having one made up, but never got to it. Have no real need of it. Thanks.

 

[tarbe]

As long as we are talking about contrasts in the loading room....

 

[Pheroze]

As long as we are talking about contrasts in the loading room....

View attachment 271011

Awe, the little guy is so cute

 

[tarbe]

So, I needed a little therapy after work today...and my therapy cat was at the vet for a tune-up...so I decided to get some loading room therapy.

I have a batch of older WW 45-70 cases that have been loaded enough times that I am now going to relegate them to trapdoor-level loads.

I wanted to load some 350gr Berry's plated with 30 grains of SR4759.

Looking at the powder inventory, I saw I had a brand new 8 pound jug, and an old metal 8 oz can with about 4 oz in it.

The can is from 1995!

So, I decided to load some up with new stuff, and some with old stuff. I will chronograph the loads to see what sort of variation I might get from two different lots, separated by 24 years!

So here is a contest...I will chronograph 5 rounds each from the new and old lots.

Members guess how much difference there will be in the average velocity between the two lots. PM your answer to me...don't post it here or people will be able to bracket themselves to increase their chances.

Winner will get bragging rights as the official AH Velocity Savant. And a genuine green onyx carved Rhino from South Africa.

I will announce the winner after I manage to get out to the range (but not before 4/1). In the event of a tie, I will have my wife randomly select a winner (somehow).

Start guessing....but only one guess per member and be sure to PM it to me!


Tim

 

[Bullthrower338]

If it’s a really sunny day and the screens are just right I guess a standard deviation of 3229 FPS! Lol

 

[tarbe]

If it’s a really sunny day and the screens are just right I guess a standard deviation of 3229 FPS! Lol

Gotta love those "magic" loads!

 

[gizmo]

So in my new building I have a dedicated reloading room haven’t had time to get it all set up yet but it’s air conditioned and heated and a whole room just for reloading!!!!!

 

[tarbe]

So in my new building I have a dedicated reloading room haven’t had time to get it all set up yet but it’s air conditioned and heated and a whole room just for reloading!!!!!

You are on your way to enlightenment, Grasshopper!

 

[Shootist43]

Is "Grasshopper" really gizmo's nickname?

 

[tarbe]

Is "Grasshopper" really gizmo's nickname?

It is now!

 

[tarbe]

Oh - and if two guys guess 50fps, but only one indicates which lot is which, then obviously it behooves you to indicate the relative positions of the new and old lots. Unless you guess wrong!

 

[gizmo]

No point, I already gave the winning estimate