Anyone had experience with this cartridge? I am thinking of building one. Any input would be appreciated.

Phantom Duck
Even in A-Square's own Manual they say that they never could get the rifle to feed properly. A 458 Lott will give you the same performance [on game any way] with a LOT [pardon the pun ] less trouble, and you can shoot 458 Win Mag in an emergency.
Just a thought.

Just push the shoulder of the 450 Dakota back .400 inches and cut it off at 2.5 inches. You get rid of the belt and the steep shoulder angle while duplicating the 460 A Square Short. This one will feed and give you 6500 FPE. This will require custom reamer and dies, but you can name it yourself and have a real live wildcat.

A more creative approach is to take the Lazzeroni 10.57 Maverick (.416 bullet diameter) to .458 and settle for 5700 FPE from a 2.8 inch action. The Maverick duplicates the 416 Rem Mag with all bullet weights. I suggest a Savage 300 WSM that you rebarrel to keep the costs down. The increase in the base diameter from .550 to .577 should still give you 3 in the magazine, and the bolt face will only need to be increased fron .532 to .577...an easy job. For serious work, the Speer 500 gr tungsten solid is quite short for its weight, and gives a lot of useful powder capacity. This is good for an extra 700 FPE in the 458 Win Mag Speer Manual #13, p 422), and it should do at least as well in this wildcat. The math says 6400 FPE and 2400 FPS.

An important key to all of this is the use of AAs 2230 powder. The fast burn rate, consistency, and high density are a perfect fit for the 458 and this wildcat application. See data in Speer and AA manuals. A light load with a 350 gr .458 spitzer at 2700 fps should give you some range if you need it. This onwe will hunt, and from a 22 inch barrel.

Let me know if you want to try it ...if not I will and will name it the 450 ATS in honor of my father who passed away last October 2nd after loving 89 years of woods and wildlife.

Sabot,
Sounds interesting, and something along the lines of what i had in mind. You will probably get there first. Maybe after you get it up I could donate a few dollars for the use and do one of my own. Naming it after your Dad seems appropriate.

l have a 460 Van Horn, basically a 460 or 378 weatherby cut at 2.50inches ran through a sizing die,well you guys probably know all this anyways,But l find that with a 26 inch barrel with a 350 grain bullet the chrony says just over 3000 fps,and a 500 grain is 2490?lve just used imr 4320 and 3031 powder,lm now wondering does this sound right to you?

There is lots of info on the. 458 accrel in my signature links.

No need for a belt

Man why re-invent the wheel. Build a 458 ACCREL, reamer, dies, brass and not to mention load data already available.