Cartridge is from Ammo Manufacture: Winchester BIG BORE 200gr SJHP (MR Revolver Guy 4/25/23)
Ballistics Information: 10mm Auto
Muzzle Velocity: 1175 fps
Muzzle Energy: 613 ft. lbs
Brass Make/Headstamp: Winchester - Brass
Bullet Make/Weight/Construction/Info; Length 0.6775?/Dia. 0.4000?:BIG BORE SJHP 200gr
HP depth ? / Inside Dia. ? tapered / mouth Dia. ?
Actual weight 200.2 grains   Crimp squeezed bullet to 0.3995?
C.O.A.L.: 1.2505?
Primer: brass color
Case: Diameter 0.4220? Crimp Diameter 0.4215? (Medium Length 0.9890?
Powder Description/Positive ID/Type/Charge ?? WAP ?  Weight: 7.9 ? 8.0 grains
Winchester Action Pistol is Similar to Silhouette  (very fine flatten ball)











Winchester load data when the were producing Winchester Action Pistol powder

Thanks Wade, haven?t seen this offering before

I actually saw those listed in stock the other day at Natchez shooting and outdoors. I went back a miniute ago and they have them still in stock. $39.99 for box of 20.   

dang! almost $2. a pop! I'm sure glad I can reload!

I'm with you Blaster. I cant imagine paying that much per round. plus im sure taxes and haz-mat fees put it more like $3 a round said and done.

Absolutely, I could load a number of my 200gr Gold Dots for that price

Yeah it was 30 bucks a box at my local shop.

Here is the video to go along with it.

https://youtu.be/vhJPOv0yCyk

Thanks mr.revolverguy, another great video. I think after watching this, I?d be better served with Underwood?s 200 Grain Hard Cast Flat Nose for large toothy critters, which would likely meet or exceed their advertised 1,250

good video Mr.Revolverguy. too bad another disappointing factory 10 mm round. why don't these ammo companies just start using Long Shot instead of their wimpy factory powders and get "real 10 mm velocity" ammo? heck, I can get 1070 fps. out of a 200 gr..45 acp bullet using Unique! (and .45 Super brass for safety) I wonder how long Winchester's test barrel is to get 1200 fps out of that wimpy load? my 200 gr. JHP 10mm with 9 gr. of Long Shot chrono around 1200 fps out of the 4.5" XDm and 1170 out of the 4" Witness bbls. they must be testing out of a carbine barrel!

As mentioned...
for that price I can load a good number of rounds. Heck, Still about .25 per.

Hi end rounds with the 200 gr XTP and some 800x gets right up to 1200 with ease. ( tho it meters like crap and must be each hand weigh )

OOOOOh speaking of barrel length maybe I can get my buddies 10MM Vector and test the rest of the rounds. I think there is 8 more rounds in that box.

Would be interesting to see what the carbine?s getting

I added this Winchester Load data from back in the day when they had the Winchester Action Pistol powder.  After Winchester discontinued that powder, this powder formulation was picked Ramshot as Silhouette.  (see added loading data)

Winchester WAP data



Ramshot Silhouette data

Thank you Shadow. I did some testing though the carbine https://dayattherange.com/?page_id=11209

thanks for the video mr.lrevolverguy.
Winchester Big Bore still looks unimpressive (other than the accuracy) to me. it should have been getting those velocities out of the 5" bbl.! maybe if they loaded it with a softer bullet it would make a good S.D round but I wouldn't use it in big bear country!
looks like those of us who want magnum performance out of our 10mm pistols still have to reload or buy "boutique" ammo.