Tumbling Rounds with 45-70

[rompus]

All my weapons are military style and decided on a whim to get a Buffalo Classic from H&R for 395.00 at Encks gun barn. At that price I figured what the heck and most reviews are very positive. I know zero about these guns or ammo so I bought a box of 405 grain Black hills ammo too. This is strictly a target gun. We set up on a hay bail @ 75 yards and my first shot was a complete miss, the next shot was a tumbler and left a keyhole (something I have never seen before) also low and to the right.Some shots hit the ground first, no amount of adjustment on the sights seemed to work,at one point I got a fairly good group. My buddy shot too with the same results but no tumblers after the first one. Also two of the bullets landed on the ground behind the 1/2" plywood and were undamaged!! The ammo was also very dirty in the bore (this is smokeless not blackpowder.)We decided to try 25 yards offhand with better results but still low (we stopped trying to adjust the sights) I cannot believe it is the rifle and am going to try a different ammo or grain but thought I would check here first. I also blew out the bore after each shot to clear the residue. The tumblers (2 of them) are the ones we think ended up behind the target.

[knight0334]

Tumbling is most often the result of too slow velocity and/or too long of a bullet for the gun's twist rate. 405gr slugs aren't all that long, all things relative, for the twist rate that the BC has(1:20"). So, it's probably the velocity that is the main issue here. With you having dirty results it sounds like there isn't enough pressure to properly burn the powder, thus a two fold issue causing lower velocities. ....incomplete burn and low pressure. They go hand in hand with each other.

The .45-70's large case and large bullet opening and a powder charge that doesn't have a good fill rate versus case capacity is probably causing alot of the powder to be blown down the bore with the bullet. At the farther end of the barrel the pressure is often 1/6 to 1/3 the pressure in the chamber just immediately after ignition.

As to the Black Hills .45-70 405gr ammo, it is a cowboy load. They are slow and low pressure to resemble blackpowder ballistics. ....so refer to the (2) paragraphs above this one.

Another possible contributor - H&R Buff Classic bores are often lightly on the large size. They range from .449"-.454" bore, and .4575"-.460" groove. Sometimes you need a larger slug than the typical .458" bullets, especially if you are shooting cast bullets. ...guess what that Black Hills is loaded with - cast.


I will bet you $5 that a box of Winchester 300gr JHP Super-X will far out perform that crappy cowboy load stuff from Black Hills.

[rompus]

Tumbling is most often the result of too slow velocity and/or too long of a bullet for the gun's twist rate. 405gr slugs aren't all that long, all things relative, for the twist rate that the BC has(1:20"). So, it's probably the velocity that is the main issue here. With you having dirty results it sounds like there isn't enough pressure to properly burn the powder, thus a two fold issue causing lower velocities. ....incomplete burn and low pressure. They go hand in hand with each other.

The .45-70's large case and large bullet opening and a powder charge that doesn't have a good fill rate versus case capacity is probably causing alot of the powder to be blown down the bore with the bullet. At the farther end of the barrel the pressure is often 1/6 to 1/3 the pressure in the chamber just immediately after ignition.

As to the Black Hills .45-70 405gr ammo, it is a cowboy load. They are slow and low pressure to resemble blackpowder ballistics. ....so refer to the (2) paragraphs above this one.

Another possible contributor - H&R Buff Classic bores are often lightly on the large size. They range from .449"-.454" bore, and .4575"-.460" groove. Sometimes you need a larger slug than the typical .458" bullets, especially if you are shooting cast bullets. ...guess what that Black Hills is loaded with - cast.


I will bet you $5 that a box of Winchester 300gr JHP Super-X will far out perform that crappy cowboy load stuff from Black Hills.

Boy that is a very logical explanation. I noticed that the recoil was very light too. Thanks for a great response. I'll donate the 5 bucks to the NRA if you are correct.

[knight0334]

You might as well write that check to the NRA.. lol

Here are some of my H&Rs/NEF's. A few others are spread out around the house, and out at the farm.

I've got a lot of experience with the .45-70 and .45-120. I have (2) Buffalo Classics - one in the original .45-70 chamber, the other I reamed to .45-120. And a .45-70 Handi rifle.



Winchester 300gr JHP Super-X is probably the best shooting factory ammo available. My 22" Handi rifle shoots ragged 1-holes at 50yards and cloverleafs at 100yrd with it. The BC mirrors the Handi's results.

Something else to consider with cast bullets... ...the BC uses Marlin's "Microgroove" rifling which is shallower that Ballard type rifling. Results aren't as good with cast as they are with jacketed bullets with Microgroove rifling.

Barnes VOR-TX and Hornady's Leverevolution ammo is also good performing and accurate stuff.

Try to stay away from any cowboy load stuff unless you load it yourself with properly sized bullets. The BC doesn't need the powder puff loads like a Springfield Trapdoor rifle needs. And with smokeless rifle powder, you actually need higher pressures for it to burn properly.

[rompus]

Nice stuff you have there. I really think the buffalo is a great value,sure they took some shortcuts but for that price they have to. I would like to shoot out to 500 or 600 yards and from what i have read the buffalo can do it. I was going to mount a creedmore to the stock based on some posts on other websites. I would probably keep the front sights. Your opinion would be appreciated.

[knight0334]

The BC will do 500 yards and more. There is a guy over at Graybeard Outdoors that shoots 1000yards with his. I use mine to shoot groundhogs with a half dozen kills over 500yrds, and my furthest at 540yrds. ...open sights.

You'll probably have to use 405gr slugs or more to do it at better than cowboy load pressures. Beyond 405grs and you'll probably have to get the throat reamed to allow longer bullets. H&R short throated the .45-70's. Anything more than 405gr and you start engaging the rifling prematurely when chambering the cartridge.


Rear sights - some folks have installed vernier tang sights on their BC's. The best way to do it is to do a cut relief in the stock and install a false tang. Then mount the sight to that false tang.

The factory sights wont adjust far enough for such long ranges, especially if yours came with the taller front globe sight. (there are at least 3 different heights for the front). The .404" high front is the one you want. Williams also makes a replacement rear that will allow 1000yrds with the .404" front(see below).

70273 FP-H&R For Buffalo Classic and Handi rifles. $74.95
70260 FP-H&R-TK For Buffalo Classic and Handi rifles. (With Target Knobs.) $86.95
http://www.williamsgunsight.com/guns...htsdefault.htm

[rompus]

Thanks brotha!!

[cephas]

Great info. There are also some specimens that have ballard rifiling, seems to depend on when it was made. (edit:Ballard rifling is 6 groove rifling, vs. the 12 groove of the Micro-groove rifling.) Have spent time with microgroove barrel and cast. It can be done but in my experience they need fat casts. Depending on velocity desired a gas check may help. From a site I saved:
"There has been a great deal of concern over the years about whether or not Microgroove rifling would shoot cast bullets well. One group of folks says that Microgroove rifles can't hit a barn from the inside with cast bullets, one group says that Microgroove barrels shoot cast just fine just so long as velocities are kept below 1600 fps, and one groups says that Microgroove barrels shoot cast just fine at full throttle. The key to success with cast bullets in a Marlin with Microgroove rifling is to keep in mind that these barrels tend to have oversized groove diameters, and that the grooves/lands are shallow. Therefore, in order to get proper engraving (and minimize "slippage" of the cast bullet as it enters the shallow rifling), it is necessary that the bullet completely fill up the groove diameter of the barrel, and engage the maximum amount of the driving surface of the lands. Since Microgroove barrels are commonly oversized, this means that the cast bullet must also be oversized to effectively "fill up" the grooves. Other factors that also contribute to good accuracy with cast bullet in Microgroove barrels are the use of a GC bullet (which helps to provide a better grip and seal), and making sure that bullet are cast hard enough for the application (generally a BHN of 12 or more). It is also worth remembering that throats in modern rifles are almost always cut larger than groove diameter of the barrel (to insure that ammunition can chamber easily), and that best cast bullet accuracy is obtained by fitting the bullet to the throat, hence reinforcing the need for oversized cast bullets in Microgroove barrels (for example, the throats on my .30-30s run almost .311", so I size cast bullets to .310" for these guns). " http://www.leverguns.com/articles/fr...ve-barrels.htm

[rompus]

I just bought some Hornady lever action, it was all I could find and it has a teflon tip and brass bullet, it was cheaper than the black hills stuff.

[bamboomaster]

I just bought some Hornady lever action, it was all I could find and it has a teflon tip and brass bullet, it was cheaper than the black hills stuff.

You could reload your own.

Now you have the brass, the're all kinds of powders depending on your mood (Swiss 1.5F for a smoker, IMR 4198 and others for a laser), and King Shooters Supply in KOP has a well-vetted supply of BHN 21 sized .459 cast boolits.

Just sayin'.....