I'm sending a sako stainless laminate in 300 wsm to be bored to a 35 wsm,I have a sako kodiak in 375 that I rarely use and have been wanting a 45 cal bolt gun for awhile.Has any had any experience with these ? I'm thinking that kodiak bored to 45 would be a nice rig to play around with.tks for any input Robin
450 ackly
- Thread starter thinhorn
- Start date
- Location
- Somewhere on the Hudson Bay Coast
IMHO, a bottleneck cartridge trumps a straight wall cartridge when used in a bolt gun, although the straight wall cartridges may have the edge in a double or a falling block. It has to do with the nature of how a big bore bolt action is used. What frequently happens is that the top round is fired and then a fresh round tops off the magazine. Each time the bolt is cycled, the rim of the ejected round catches on the mouth of the top round on the magazine, and it doesn't take long for that cartridge to get pretty beat up and start causing feeding problems. The only cure is to choose bullets with deep crimping grooves which allows the case mouth to form a rounded forward surface rather than a sharp edge. This is one reason why I tend to go load TSXs in my .458.
The .450 Ackley doesn't have much of a shoulder, but its enough to solve the problem common to the Winchester and Lott cartridges, even though the former shares a common head size with the latter. According to Ackley, the straight wall design of his version provides a sufficient increase in capacity that he achieved 300 fps over typical .458 Winchester velocities. In 1960, I don't think the factories had reduced their .458 loads to hot .45/70 levels. Someday I'll convert my .458 to a .460 Ultra, and just expand my .375 Ultra necks to .458. Thus I could match or slightly exceed Lott velocities without the disadvantages of running a straight wall case in my M-70.
The .450 Ackley doesn't have much of a shoulder, but its enough to solve the problem common to the Winchester and Lott cartridges, even though the former shares a common head size with the latter. According to Ackley, the straight wall design of his version provides a sufficient increase in capacity that he achieved 300 fps over typical .458 Winchester velocities. In 1960, I don't think the factories had reduced their .458 loads to hot .45/70 levels. Someday I'll convert my .458 to a .460 Ultra, and just expand my .375 Ultra necks to .458. Thus I could match or slightly exceed Lott velocities without the disadvantages of running a straight wall case in my M-70.
I see what you're saying, but I don't necessarily agree for a couple reasons.
I've never noticed the issue you're speaking of in my Lott chambered BRNO 602
Every time I reload, I trim the cases so that I have a uniform crimp. The trimming would clean up any damage if there was any.
That being said, I think the 458 Ackley is a cool round for the sake of being different, but Lott components are much easier to obtain.
I've never noticed the issue you're speaking of in my Lott chambered BRNO 602
Every time I reload, I trim the cases so that I have a uniform crimp. The trimming would clean up any damage if there was any.
That being said, I think the 458 Ackley is a cool round for the sake of being different, but Lott components are much easier to obtain.
So it's been suggested that 458 Lott is more practical from a component and ammo availability perspective. But I say If you like the idea of the 450 Ackley just do it, it's a great round. You can get more power from the Ackley than from the Lott, and in a pinch you can shoot 458 Lott or 458 Win Mag ammo. Plus you can make brass from .375 H&H if you want to, just like you can for the Lott or the Win Mag.
You may want to read this article on the 450 Ackley by Zimbabwean professional hunter and gunsmith Roy Vincent, if you haven't done so yet.
http://www.africanoutfitter.com/backissues/2007/junejuly/450ackleymagnum.php
You may want to read this article on the 450 Ackley by Zimbabwean professional hunter and gunsmith Roy Vincent, if you haven't done so yet.
http://www.africanoutfitter.com/backissues/2007/junejuly/450ackleymagnum.php
I had a 450 Ackley for many years on a 602 Brno, it is a fun cartridge even if I had to stock it 3 times. Components are not at all difficult to get, you just make your brass from 375 H&H or even better from 416 Rem. You can buy dies from Huntington in the US and yes they ship to Canada, no problems. The Ackley is capable of an honest 100 fps better that the Lott and 400 fps over the 458 Win. In a 9.5 pound rifle the free recoil at 2550 for a 500 gn bullet is 93 pounds and the energy exceeds 7000 ft lbs. It's a blast to shoot and separates the boys on the range real fast, always take an extra 10 rounds to the range 'cause there are always guys who just gotta try it. My 450 would shoot clover leafs as long as I did my part and this never changed through 2 barrel bobbing incarnations.....26" to 22" to 20". Never got to chronograph the 20" final configuration, but only lost 90-100 fps from 26 to 22". Sorry but I don't recall which powder I used, but there is probably a better one now, as that was 25 years ago. I was going to use it on my very first Safari for my buff but it shed it's stock one day while practicing a mere 2 weeks before departure so I ended up taking my 416 Taylor instead. Unfortunately I never killed anything with it before we parted company.
I would recommend it whole heartedly, just for the fun factor.............
I am currently working on a 458 based on the 375/416 Ruger case, which I have high hopes for. Won't likely reach the Ackley level of performance but should equal the Lott and possibly slightly better. I have a donor rifle in 458 WM and my reamers, but I am now separated from my lathe for the winter..........unless I buy a new one.........HHHMMMMM....
Boomer.....I have never experienced the rim/case mouth problem you have alluded to, but in my various 458s I have always crimped into the cannelure heavily, even my Ackley so I've never had this issue. With this and usually heavily compressed powder charges I have never had bullets driven into cases either, which I'm told by another 602 Ackley shooter will happen quite frequently if you don't crimp. What with 5 under in the 602, I believe him. That's a lot of magazine slam for that 6th round.
I would recommend it whole heartedly, just for the fun factor.............
I am currently working on a 458 based on the 375/416 Ruger case, which I have high hopes for. Won't likely reach the Ackley level of performance but should equal the Lott and possibly slightly better. I have a donor rifle in 458 WM and my reamers, but I am now separated from my lathe for the winter..........unless I buy a new one.........HHHMMMMM....
Boomer.....I have never experienced the rim/case mouth problem you have alluded to, but in my various 458s I have always crimped into the cannelure heavily, even my Ackley so I've never had this issue. With this and usually heavily compressed powder charges I have never had bullets driven into cases either, which I'm told by another 602 Ackley shooter will happen quite frequently if you don't crimp. What with 5 under in the 602, I believe him. That's a lot of magazine slam for that 6th round.
I've mulled over the possibility of a 458 Ruger many times, but I decided it wasn't going to happen beacause it would have the same headspace troubles as the 400 Whelen and 411 Hawk type cartridges.
I'm interested to see your take on it. I bet it will be a cool cartridge.
I'm interested to see your take on it. I bet it will be a cool cartridge.
Bg45-70..........I addressed the potential headspace issues by going to a 40 degree shoulder, but I'm fairly certain the 30 degree would have been fine. There is quite a significant shoulder with a measurement of .515 @ the shoulder and an outside neck dia of .475-.476. The 400 Whelen works fine with a 40 degree shoulder too. It's the lousy 17.5 degree shoulder which is the problem.
I like the 450 Ackley, think it's the best of the H&H based 45's. If you think of the Ackley as a 22 LR , you can use 458 WM in it like 22 Shorts in a LR, and 458 Lott like 22 Longs. It doesn't give you a lot more in terms of performance over the lot, but I'll take whatever I can. - dan
Yep Dan that's true but you do get funny looking cases........458 WM with about a 100 thou neck and the Lott with a little longer neck. I have done this and they both iron out just fine through the sizer die. In my 602 Ackley they all shot close enough to save one's a$$ at 50 mtrs and less.
I'm thinking my next biggy after this 458 Ruger Imp (or as someone other than me suggested the 450 Douglas Express) might just be 475 on a shortened Rigby case, down to about 2.65 or 2.70 maybe..........got the barrel already so what the heck. I'm pretty sure I paid Dave for the last batch of reamers so he'll probably make me some more. Just whack the barrel off my 602 in 416 Rigby and thread on the new one for playing purposes.............hold the boat, I think I might have ordered that reamer years ago from JGS when I first designed it, guess I'd better check through my reamers before I order it twice..........now that would be stupid !!!!
I'm thinking my next biggy after this 458 Ruger Imp (or as someone other than me suggested the 450 Douglas Express) might just be 475 on a shortened Rigby case, down to about 2.65 or 2.70 maybe..........got the barrel already so what the heck. I'm pretty sure I paid Dave for the last batch of reamers so he'll probably make me some more. Just whack the barrel off my 602 in 416 Rigby and thread on the new one for playing purposes.............hold the boat, I think I might have ordered that reamer years ago from JGS when I first designed it, guess I'd better check through my reamers before I order it twice..........now that would be stupid !!!!
