Loading a bit for my 71 Winchester today having finally shot up my stash of original Win factory loads and a batch of reloads that came with the rifle from the seller.
Now I set here with 80 some empty cases and Mule Deer's "The Big Book of Gun Gack" open to the section about 348s. Seems that my powder options for today are---

Reloader 15, I have it on hand and will be trying it with 200 gr Hornadys. check

IMR 4350, the book shows H4350 with the 200 grainers. (any potential problems crossing data there?

IMR 4831 finding no listed loads with 200 Hornady's there.

So I am looking for info on loading the IMR 4350 and the IMR 4831 with 200 grain Hornady's

This is a " real time" post starting now. going to start with 3 shots with 55, 56, 57 gr of Rel. 15 across the chrony then hopefully move on to the next powder. Any recommended proven safe loads with the other two powders would be much appreciated.

Varget for the 200gr Hornadys and H4350 for the 250s. F-210 primers.

well the tale of the chrony so far shows.


Reloader 15,, 200 gr Hornady, 55 grains average 2469 fps, 56 grains average 2485 fps, 57 grains 2520 fps. (2 shots with 55, 3 shots each for 56 and 57 gr)

I was surprised how little fps change two grains of powder gave me in this first testing of the loads for this rifle.

Using a 200 grain FTX, CCI 250 primer I worked up to 60 grains IMR 4350.

The primers were protruberant at the lower loads then looked " better" from 58.5 to 60 grains.

H 4350 data is different than the IMR.....The H 4350 .calls for more grains.

I never used IMR 4350 Before, my powder meter machine loved it! The 71 also hit everything the peep sighted in deadcenter.

The web sight Terminal Ballistic Research promotes superior velocity using Superformance powder, but no data published.

Looks like the burn rate on superformance powder is right next to H 4831.

I have an original model 71, hoping to get a mirkou carbine someday to explore velocity performance, I am not that Keen on hot rodding the ol girl I got. With out a scope what's 75 fps among peeps?

It’s a big darned case! Sounds like you’re getting good speed though.

I’ve never used anything but RL17 in mine but any of the book data out there is pretty danged good.

I use RL-15 with 235gr. cast bullets at 2100fps. When I shot jacketed bullets years ago IMR or H 4350 and RL-19 gave top notch velocity and accuracy in any of my rifles. I own a mix of original and Browning reproductions.

My one and only load was the Hornady 200gr FP over 60gr IMR4350, WW brass and LR primers.

Gents, I have an EXTENSIVE spread sheet for this caliber. Anyone interested, PM me your email address. For me I settled on 56.5gr of Varget for the 200s and 58gr of H-4350 for the 250s. These were recommended to me by Mule Deer. Primers were WLR.

I've got JorgeI's spreadsheet somewhere from a while back. Crazy amount of data.

My Browning 71 likes the 200gr FP Hornadys' over 59.0 gr of IMR-4350. Don't recall which primer. 1/2" to 3/4" group at 50 yards with irons. Best my eyeballs can do. YMMV.

I went with IMR cause I could not find H4350 at the time. It likely makes some difference, but I'll never know.

Many thanks to all here. I am sorry to have dropped off the map after this post started. (been out on a job) But today I am back at the loading bench, now armed with a bit more information to go with. Looks like I will be trying some IMR 4350 and some more with the Reloader 15. Am still trying to find data for 4831 with the 200 grainers.
Will be requesting JorgeI's spread sheet today also. Again, many thanks!

One more thing, I am wondering about. Case life. I have never loaded for a bottle necked lever gun before. Would it behoove me to neck size the cases rather than full length resize them? I am wanting to maximize case life for this particular rifle. Thanks

my browning 71 loves 58 gr. IMR 4350, CCI 200 primer 200gr hornady and just like gun geezer shoots all touching at 50 yards with a williams receiver sight.