600 yd. 45-70 load for Marlin Cowboy

[rvpilot76]

Do you think that a 405 grainer @ around 1700 fps would be enough? I'd like to stretch her legs a little. Plus, I just love plinking at long range! :-D

Kevin :lovebooli

[xND]

In 1879 shooting trials were held at Sandy Hook, NJ, trying the .45-70 at two miles (3400 yds)and read all about it Yjese trials lead to the adoption of the 500 gr infantry bullet for the trapdoors..

. You can find the article on the internet under the above title

Yes, the .45-70 will reach out a distance and still remember what it was sent out to do!

xND

[Wayne Smith]

And that was done with a case full of BP. Yes, you can. The heavier bullet the better for the longer ranges, but the heaver bullet the more the recoil, too. If you don't have one, get a PAST pad! BuffaloArms.com, Midway.com, etc. to find one.

[kodiak1]

rvpilot76 If you are just plinking it will do it. Have done it with 375 GRN over 24 GRNs of 5744 in my 40-90 and I don't think that I was getting that kind of fps, just guessing at about 1400 will use the Chrony next time for sure.
Ken

[Larry Gibson]

Do you think that a 405 grainer @ around 1700 fps would be enough? I'd like to stretch her legs a little. Plus, I just love plinking at long range! :-D

Kevin :lovebooli

That will work fine, however you don't need to push it to 1700 fps to "plink" at 600 yards. I do some serious long range shooting with my H&R Officer's Model Tradoor out to a few hundred more yards past 600 with Lymans 457124 (408 gr wiith my alloy) over 35 gr of milsurp 4895 and a 1.5 gr dacron filler. It runs right at 1350 fps and shoots into 1 1/2-2 MOA. I've also used the simular Lyman bullet, 457483, with GC at 1693 fps (46 gr of ms4895 and no filler) out of my bolt gun 45-70 at longer rangers. It shoots just as well but the recoil gets a little obnoxious when "plinking".

You'll do fine and have fun.

Larry Gibson

[Blackwater]

At long range, velocity variations at BP velocities come into play significantly in your vertical dispersal. It'll most likely take some serious testing to get your SD's low enough for you and the rifle to do your best at that distance, but it's one heckuva' lot'a fun. Extra velocity, up to a point, really doesn't help as much as you'd initially think, so if you find a mild load level, say at BP velocities, gives you the best results, don't think twice, and be grateful for the lowered recoil level. That'll let you shoot a lot more, and to connect at long range WILL most likely take a significant amount of shooting. And when you shoot, try to learn something from every shot. It's a fascinating and VERY enjoyable pursuit. If a shot lands other than where you expected it to, always try to find out why. The more you shoot, the better you'll get, up to a point. When that happens, you'll likely make strides intermittently, as you discover the subtleties of how the gun wants to be held, etc., etc., etc.

Oh yeah. Be SURE to get a spirit level front sight. It REALLY matters when you get way on out yonder, and I doubt there's many who can shoot at long range consistently without one. It shocked me the first time I found out how much difference it made, and that was only at 300!

[PatMarlin]

600 yrd plinkin' with my Guide Gun?... I'm There!! :Fire: [smilie=1:

[Bucks Owin]

Just remember to tilt that muzzle waaaay up....

( kinda like a mortar! ) :-D

Dennis

[PatMarlin]

You just gave me an idea with that mortar... :drinks:

[Larry Gibson]

rvpilot76

I forgot to mention one critical thing; sights! You'll need a rear sight with considerable elevation. All jokes aside it actually would require less sight elevation with the Guide Gun because of the shorter sight radius than your Cowboy model. I've shot to 600 yards with my trapdoor carbine with 1879 rear sight without problems and actually pretty good accuracy. I shoot a 405 gr bullet at 1150 fps in it. Anyways, a tang sight or Lyman reciever sight will be needed to do justice to any long range shooting. A Winchester type rear sight for the M1886 with elevation ladder also will work nicely. Have fun.

Larry Gibsin

[McLintock]

Several years ago, when I was developing loads for Long Range Cowboy Action shooting for both a Browning 1885 Hi Wall and a 1886 lever gun in 45-70, I did quite a bit with the 405 gr'er at 500-550 yards. All loads were with smokeless powder and hard cast bullets, but the thing I found out the most was that the 405's become very unstable out at those distances. Many were going through the target at odd angles and a few even sideways; and these same loads were no problem at up to 3-400 yards, in fact could be quite accurate with the right load. Currently I'm shooting the 45-70 with 500+ gr bullets and black powder and don't see that problem. Don't know if increasing your velocity to the stated levels will help or not, but it'll sure be noticicable on the butt end of the gun. Those lightweight guns and a healthy 45-70 load don't go together too well for the shoulder. Just my experience.
McLintock

[Scrounger]

RPM is the number that controls bullet stability. And both Rifling Twist and Velocity are the factors that make up RPM. Your load was sweet at 400 yards but at 500-550, it had slowed down so much the RPM number had dropped too low to stabilize the bullet. Yes, you can increase the velocity to bring bullet stability up to get accuracy at that range, but at the cost of a sore shoulder. A more pleasant way to do it would be to get a barrel with a little faster twist. A lighter bullet would achieve that also, at least in theory, but it would be more wind sensitive and have less knock-down power out there, if that is important.

[McLintock]

Scrounger,
Doesn't sectional density, lenght vs diameter, of the bullet itself have a lot to do with stability out at extended ranges? A higher SD bullet is supposed to be more stable, but you need a faster twist to increase the RPM as you have stated. Going to a lighter bullet just reduces the SD, so basically defeats your needs out at long ranges, although they certainly reduce felt recoil. I never had much luck at all with 300 gr 45-70 bullets, no matter how fast they were driven. The 405's were starting out at about 1450-1500 fps, which isn't too slow for a 45-70, and were becoming unstable due to both shortness of the bullet and loss of rpm at the extended distances. Just my best guess.
McLintock

[felix]

1000 yards typically requires a 500 grainer using a 18 twist. Ammo was delivered in the old days with the 500 grainer, but the pitch was still at 22. ... felix