The 470 Capstick Pt.2

[CZDiesel]

My rifle shoots both the Barnes Banded Solid and the Barnes TSX 500gr bullets to the same point of aim at 50yrds with 72gr H4895.
This load gives 2260ftps with the TSX and 2290 with the Banded Solid…

 

[krish]

Thank you. Some thing to go by for base line in my rifle.
Krish.

 

[krish]

I do havd Aframes and Hornady bullets. So for I favor 450 Rigby. We will see.
Krish

 

[1dirthawker]

My mind is still blown that it’s pushing a 500gr Barnes Banded solid over 120fps faster than the 458WinMags 500gr Hornady DGS and it seriously feels as if it has half the recoil! It was on par with the 450/400.

hi,

just curious. is the 458 win rifle lighter than the 470 capstick? it seems weird that it kicks much less than the 458 and getting an additional 100 fps out of a 500 gr bullet, both are in a straight case, powder charge can't be a lot different, so am curious about the substantial recoil difference. any ideas as to why?

 

[Ray B]

I have a problem with the 470NE. The gun is a vintage Rigby and I've read that it can be damaged by shooting hard, as in steel jacketed bullets. Now I have a few hundred Hornady steel jacketed, copper coated .474 bullets. I have sufficient Woodleighs and cast bullets for use in the Rigby so what to do with the bullets that could injure the old rifle? I'm leaning toward purchasing a single barrel .470. Either the regular production .470 Capstick or if I can only get a .470 barrel by rebarreling a standard action, a .470/.458. I really would prefer purchasing another rifle rather than selling the components.

 

[krish]

@Ray B
470 capstick is expensive comparably. May be selling some of the 474 bullets and investing that to buld one on a proper action might be an Idea.
I do have a original unfired Asqure built 470 capstick. For the right price you may talk me out of it. Yes have properly head stamped beass and dies.
Krish.

 

[krish]

hi,

just curious. is the 458 win rifle lighter than the 470 capstick? it seems weird that it kicks much less than the 458 and getting an additional 100 fps out of a 500 gr bullet, both are in a straight case, powder charge can't be a lot different, so am curious about the substantial recoil difference. any ideas as to why?

The reson might be ythat there is more volume in the 570 barrel than the 458 barrel. It might ease the pressure and increase the space for the owder to expand quickly.
Just a thought.
Krish

 

[CZDiesel]

hi,

just curious. is the 458 win rifle lighter than the 470 capstick? it seems weird that it kicks much less than the 458 and getting an additional 100 fps out of a 500 gr bullet, both are in a straight case, powder charge can't be a lot different, so am curious about the substantial recoil difference. any ideas as to why?

The reson might be ythat there is more volume in the 570 barrel than the 458 barrel. It might ease the pressure and increase the space for the owder to expand quickly.
Just a thought.
Krish

Hey @1dirthawker, Both rifles weigh the same. I think what @krish says has some merit to it but I think it’s mostly the slap the 458 gives vs most other DG cartridges. The speed that it comes back on you is serious and I attribute this to the pressures they load the 458 at. Most 458 cartridges are loaded to 60,000psi or more where as the 470 Capstick load I have is only in the 49,000psi range.
Now if I were to load the 470 to its true potential of over 2,400fps the pressures would go way up and I’m sure it would knock you around like the 458 but why? It shoots like a dream now and still has 100 to 150fps over the 458WinMag so I’m happy to keep it where it’s at.
Of course all this is just speculation on my part but I believe this is the correct answer…

 

[Ray B]

There are two aspects of recoil: the closed system and the open system. The closed system occurs from the outset of the primer firing and continues until the bullet clears the muzzle. During this time the balance point of the rifle shifts forward similarly to the weight on a balance beam scale. If you could have a loaded cartridge in the chamber and were able to locate the balance point, mark it; then move the bullet to the muzzle and distribute the powder evenly from cartridge base to bullet base, then locate the new balance point, mark it. Measure the distance. If the muzzle velocity is 2000 fps and the bullet travels 2 feet through the bore- using a constant rate of acceleration the average speed is 1000 fps which means it takes 2/1000 second. the gun will want to move the measured distance in 1/500 second. That is just the start, then the open system kicks in with the propulsion effect.

 

[Jefferry404]

@CZDiesel
This thread got my interest. The only barrel blanks I can find are 0.475 caliber. I would think the .474 calibers be ok? Thanks
Steve

 

[Luvthunt]

Interesting thread

 

[1dirthawker]

Hey @1dirthawker, Both rifles weigh the same. I think what @krish says has some merit to it but I think it’s mostly the slap the 458 gives vs most other DG cartridges. The speed that it comes back on you is serious and I attribute this to the pressures they load the 458 at. Most 458 cartridges are loaded to 60,000psi or more where as the 470 Capstick load I have is only in the 49,000psi range.
Now if I were to load the 470 to its true potential of over 2,400fps the pressures would go way up and I’m sure it would knock you around like the 458 but why? It shoots like a dream now and still has 100 to 150fps over the 458WinMag so I’m happy to keep it where it’s at.

you might be right, i would not want to bet a bunch of cash either way. my 458 win is loaded (400 gr bullet at 2450 fps) and the reload guides says it is around 49,000 psi as well. H-4895 powder. that much increase in velocity would seem to give an increase in recoil. especially, as you noted, that if you ran your 470 to a higher velocity that you would expect a sizable increase in recoil.

regardless, if it kicks less, good on ya. just means you will shoot it better.

 

[CZDiesel]

you might be right, i would not want to bet a bunch of cash either way. my 458 win is loaded (400 gr bullet at 2450 fps) and the reload guides says it is around 49,000 psi as well. H-4895 powder. that much increase in velocity would seem to give an increase in recoil. especially, as you noted, that if you ran your 470 to a higher velocity that you would expect a sizable increase in recoil.

regardless, if it kicks less, good on ya. just means you will shoot it better.

You have to remember that 458WinMag holds 95gr water, the 458 Lott holds 110gr water, and the 470 Capstick hold 117gr water.
This extra case capacity helps keep pressure down but also changes burn rate I’d assume?
And I think this is why it acts like it does? Again just my speculation…

 

[CZDiesel]

So there has been enough interest in not only this thread but in the 470 Capstick in general that I thought more load development should be shared?!?!
So I’ve decided to see what the upper limits of the 470 Capstick are? As we all know what it is doing now in my 24”bbl Winchester “Big Five” rifle.
I’m at 2290 with 500gr Barnes Banded Solids and 2260 with 500gr Barnes TSX now for hunting. One of course could still have it loaded down to 2150 with a 500gr that would match the 470 NE and the 458WinMag and probably have less recoil than a 375 H&H!
Soooo let’s see what the 470 Capstick can do when pushed and what happens to that relaxed recoil! I’m kind of scared lol
Give me a week or so and I’ll post up what it can do when pushed!

 

[CZDiesel]

I do havd Aframes and Hornady bullets. So for I favor 450 Rigby. We will see.
Krish

@CZDiesel
This thread got my interest. The only barrel blanks I can find are 0.475 caliber. I would think the .474 calibers be ok? Thanks
Steve

Interesting thread

@Jefferry404 PacNor lists that as a 470 Capstick bbl so I’m guessing it should be good but talk to them. Also look at Douglass and Shilen…
Kevin Weaver at Weaver Rifles here in Colorado Springs has built several of these so I’d recommend calling him for more advice as he has actually done it! And he’s very good!!!
This is such an amazing performing DG cartridge that nobody knows about! Would be a very fun and rewarding rifle build!

 

[Jefferry404]

@Luvthunt
I did search all the barrel makers. PacNor chambers for the Capstick but their barrel caliber list at 0.475 and Douglas barrel says 475 Linebaugh and list caliber at 0.475.
I did speak with Hornady Monday they confirmed the 470 Dgx,s are exactly at 0.474 +-1/10000.
I know Kevin. He rebarreled to a 338-06 for me.
Thanks

 

[CZDiesel]

@Luvthunt
I did search all the barrel makers. PacNor chambers for the Capstick but their barrel caliber list at 0.475 and Douglas barrel says 475 Linebaugh and list caliber at 0.475.
I did speak with Hornady Monday they confirmed the 470 Dgx,s are exactly at 0.474 +-1/10000.
I know Kevin. He rebarreled to a 338-06 for me.
Thanks

Kevin is a good guy and as you already know a great rifle maker! I talked to him today and told me that a .475bbl will work fine for .474 Bullets…

So I was going to see what the upper end of the velocity spectrum was for the 470 Capstick and to see what it was possible of energy wise. But when I told Kevin this he said “why on earth would you want to do that lol”
I in turn told him it was just academic, to see what the 470 Capstick was capable of…
Kevin said “no need!” He has built multiple 470 Capstick riles on Winchester Pre-64 actions using Krieger bbls that measured .474 and has done a ton of load work for them. He pulled his files for it and told me he had worked up to 2460ftps with an 500gr bullet out of a 23” bbl for 6718ftlbs of energy!
With the 24”bbl on my 470 I’d guess I’d get 2475ftps maybe more? That gives it 6800ftlbs of energy!
With more work with different powders or blended powders I’d think 2500ftps or better is obtainable? This would give you 6938ftlbs of energy! This type of energy and bullet dia puts it in the 500 Jeffery and 505 Gibbs class energy wise…
Kevin said he had tried to duplicate these load levels in the 458 Lott but couldn’t do it, it resulted in blown primers. The extra case capacity in the 470 Capstick and the larger bore brings the pressure down to work in those areas.
Again, why though? It’s nice knowing it’s capable of it but where it really shines is working in the 458 Lott range that gives you recoil in the 375 H&H range! That’s the magic!
The more I work with and dig into the 470 Capstick the more I love it for a DG cartridge! It can be loaded down to 458WinMag levels and it’s a pussycat to shoot or up to the range of the 50’s and it’s a monster!
When I asked what the recoil was like on the 2460ftps load vs the 2290ftps load I have and he said night and day! He said the 2460ftps load is the worst recoil he ever felt and he’d never do it again! That’s what the extra 200ftps does to a mild shooting cartridge pushing 500gr bullets!
Hope I’m not boring everyone with my feedback from my rifle and loads lol

 

[Jefferry404]

Kevin got back to me as well regarding the 475 caliber barrels.
The increase bore and case capacity helps. To show this, I use QL (which is great for relative studies)
by fitting AA 458 Lott data, adjusting WF and Ba (my std reloading method and also recommended by QL author) to match the velocity and pressure. Then increase caliber to .474 and then add the increase case capacity. Then, use 500gn bullet with the above and 24" barrel. Results are below:

458 lott case is 110gn
470 capstick case is 114gn
fit AA data for 458 lott h4895 max
using barnes 450gn solid length increased by 465/450

H4895_465gn velocity pressure
std 458 lott 26" 2410 fps 62400 psi
to .474 caliber 2375 fps 57323 psi
to 114gn case 2332 fps 51591 psi
with the above 2410 fps 57839 psi
with the above 2462 fps 62400 psi

H4895_500gn
std 458 lott 24" 2252 fps 62400 psi
to .474 caliber
to 114gn case 2301 fps 62400 psi

for both cases, the larger caliber and increased case capacity gives about 50 fps more
in the 470 vs the 458.

I should note regarding stretching the load for even higher velocity that it is not just the case
or bolt pressure signs but the barrel stresses (I design integral barrels with custom contours and
go thru that analysis for each design). Not sure of the Model 70 barrel contours but using Winchesters safari contour, at the levels above, are stressing the barrel.

Steve

 

[CZDiesel]

Kevin got back to me as well regarding the 475 caliber barrels.
The increase bore and case capacity helps. To show this, I use QL (which is great for relative studies)
by fitting AA 458 Lott data, adjusting WF and Ba (my std reloading method and also recommended by QL author) to match the velocity and pressure. Then increase caliber to .474 and then add the increase case capacity. Then, use 500gn bullet with the above and 24" barrel. Results are below:

458 lott case is 110gn
470 capstick case is 114gn
fit AA data for 458 lott h4895 max
using barnes 450gn solid length increased by 465/450

H4895_465gn velocity pressure
std 458 lott 26" 2410 fps 62400 psi
to .474 caliber 2375 fps 57323 psi
to 114gn case 2332 fps 51591 psi
with the above 2410 fps 57839 psi
with the above 2462 fps 62400 psi

H4895_500gn
std 458 lott 24" 2252 fps 62400 psi
to .474 caliber
to 114gn case 2301 fps 62400 psi

for both cases, the larger caliber and increased case capacity gives about 50 fps more
in the 470 vs the 458.

I should note regarding stretching the load for even higher velocity that it is not just the case
or bolt pressure signs but the barrel stresses (I design integral barrels with custom contours and
go thru that analysis for each design). Not sure of the Model 70 barrel contours but using Winchesters safari contour, at the levels above, are stressing the barrel.

Steve

Great info, thanks for the post and analysis