Author Topic: Buffalo Classic 45-70 accuracy problem (Read 2473 times)

StevenK11 · « **on:** July 12, 2009, 07:09:57 AM »

My 45-70 Buffalo Classic has not given me the accuracy that I would have expected. So far, I've owned the rifle for 2 years now, and have not seen groups any better than 4" @ 100 yards; and even then there were flyers almost every 5 shots and most other shots were random and looked more like a shotgun pattern.

This has given me an interesting project to get this rifle to shoot accurate. Here are the details on what I've done so far:

- Shooting 300 and 405 grain cast bullets. .459 diameter.
- Powders used... IMR 3031, 777 black substitute, and Hodgdon Universal (similar to Unique) for light loads. Note: no grains are being listed to keep this thread safe; but the loads used varied from starting to middle power loads of 1200-1600 fps.
- Changed out the rear sight and put on a quality lyman target knob adjustible rear sight.

Now to the interesting part: The final straw on this rifle was when a bullet lodged in the barrel. The load was IMR 3031 and was near the starting load, but not the bottom. I had to hammer the bullet out with a wood dowel. It was very difficult to get the bullet out too. Afterwards, I set the rifle and stuck bullet aside for about a half year after and did nothing with it.

Recently, I came back to working on the Buffalo Classic and decided to measure that stuck bullet to find out what it slugged to in the barrel. It measured .456 exactly !!! This has led me to believe I have a very tight barrel on my classic and need to shoot a smaller cast bullet; like .457. I also found out that Lee makes a bullet sizer kit that fits on a single stage press (used for folks who cast their own bullets). It lets you resize cast bullets and lube them too with alox. The kit is available in .457.

This kit is on the way and I hope to be able to test it out in the coming weeks. Anyone else have experiences with a tight barrel and matching the correct cast bullet? I’ve also heard that you should be .001 larger, but .003 seems to be pushing it in my situation.

quickdtoo · « **Reply #1 on:** July 12, 2009, 08:44:35 AM »

First of all, I'd be suspect that the 3031 load was short charged or contaminated, Lyman lists 48gr 3031 for a 292gr cast bullet at 11.4kcup and 34gr 3031 start for a 405gr cast bullet with a pressure of 11.1kcup, I find it hard to believe that pressures like that would fail to push even a tight cast bullet thru the bore. I'd slug the bore using the methods listed in the FAQs, slug it near the chamber end and near the muzzle, being sure to push the muzzle slug out the muzzle end, every H&R barrel I've slugged is .0005" larger at the muzzle than the chamber end, some have been reported much larger than that and should be replaced, H&R's standard of accuracy is 2" or smaller 3-shot 100yd groups at 100yds with factory ammo. The Lyman Cast Bullets Handbook states cast bullets should be .001-.002" larger than the groove diameter of the bore. Be sure to read the Handi Basics 101, there are several other reasons for inaccuracy, the most common being oil/solvent on the latch and/or shelf.

Tim

JonnyC · « **Reply #2 on:** July 12, 2009, 09:36:59 AM »

PROBLEM- THERE AIN'T NO STINKIN PROBLEM. LOL.

My 2 are as accurate as any firearm I own.

StevenK11 · « **Reply #3 on:** July 12, 2009, 10:40:28 AM »

Thanks for the help. Since you've listed powders, thought I'd list a few of mine. None have delivered anything better than 4" so far. I have used the 3031 and Varget with other calibers.

One other powder I tried, Varget. I'll do some more measuring on the barrel too. The stuck bullet measured .456.

Few of my loads:

45-70 Govt.   Laser-Cast 405gr RNFP   Varget   40.0   CCI LR
45-70 Govt.   Laser-Cast 300gr RNFP   Varget   45.0   Wolf LR
45-70 Govt.   Laser-Cast 300gr RNFP   IMR 3031   40.0   Wolf LR
45-70 Govt.   Laser-Cast 300gr RNFP   IMR 3031   47.0   Wolf LR
45-70 Govt.   Laser-Cast 300gr RNFP   Universal   13.0   Wolf LR

stimpylu32 · « **Reply #4 on:** July 12, 2009, 11:20:34 AM »

StevenK11

Some things I would look at with the stuck bullet , it could have been a weak primer , I have had that happen before were the primer did not fully light the powder charge , or it could have been a case of no powder in the cartridge . It happens to the best of us , so please don't take it personal .

The Lee sizers do work very well , but you need to use the Alox before sizing per the instructions , also you may want to step up the bullet speed for better groups .

stimpy

quickdtoo · « **Reply #5 on:** July 12, 2009, 11:27:30 AM »

I've used a .410" Lee bullet sizer to resize .416" jacketed bullets to .412"(jacket spring back) for my .405 Win H&R, it works perfect, but I use Lee case lube instead.

Tim

StevenK11 · « **Reply #6 on:** July 12, 2009, 11:30:21 AM »

Re-slugged both the breach and barrel end.

Breach: .4555
Barrel end: .456

Yes, I am using rather light charges, but when I stepped it up to 1600 fps, the groups didn't improve and my shoulder went down-hill.

I'd like to stick around 1300 fps, if possible. The steel plate on the stock doesn't help with recoil obviously, and I tried a slip-on recoil pad too, but in the end I didn't like the looks of covering up all that beautiful wood and plate. Guess I can't have it both ways, yet the original 45-70 traveled around those speeds and took out bison just fine.

StevenK11 · « **Reply #7 on:** July 12, 2009, 11:35:44 AM »

Quote from: stimpylu32 on July 12, 2009, 11:20:34 AM

StevenK11

Some things I would look at with the stuck bullet , it could have been a weak primer , I have had that happen before were the primer did not fully light the powder charge , or it could have been a case of no powder in the cartridge .

Weak primer is very possible. The case had a charge, as I manually check each case with a flashlight before loading. Also there was powder residue when I pulled the case out. Noticed some unburnt powder, so the weak primer scenario has merit.

I'm not focusing as much on the stuck bullet anymore as I am on the tight barrel, which is something more concrete that I can work with (measured .4555 - .456). With something like that, resizing a bullet down to .457 might be worth a try. Either way, the Lee sizer is in the mail. At $15, it's worth a try.

stimpylu32 · « **Reply #8 on:** July 12, 2009, 11:45:57 AM »

Quote from: StevenK11 on July 12, 2009, 11:35:44 AM

Quote from: stimpylu32 on July 12, 2009, 11:20:34 AM
StevenK11

Some things I would look at with the stuck bullet , it could have been a weak primer , I have had that happen before were the primer did not fully light the powder charge , or it could have been a case of no powder in the cartridge .

Weak primer is very possible. The case had a charge, as I manually check each case with a flashlight before loading. Also there was powder residue when I pulled the case out. Noticed some unburnt powder, so the weak primer scenario has merit.

I'm not focusing as much on the stuck bullet anymore as I am on the tight barrel, which is something more concrete that I can work with (measured .4555 - .456). With something like that, resizing a bullet down to .457 might be worth a try. Either way, the Lee sizer is in the mail. At $15, it's worth a try.

Ya I have a few of the Lee rigs , one I use to take .430 bullets down to .427 and it works well , just remember to clean it every so often or you could be going down too much .

stimpy

spinafish · « **Reply #9 on:** July 12, 2009, 12:00:33 PM »

Use the slip on pad when shooting and take it off after the range session..I have a slip-on Decellerator pad that gets used alot at the range, but gets taken off while gun is in cabinet.

wtroger · « **Reply #10 on:** July 12, 2009, 03:36:01 PM »

For all my 45-70 loads I use imr 4198. On the trap door I shoot a very light load and to insure they light off well I put half a sheet of toilet paper over the powder charge. My guess would be your load squibbed.

45-70.gov · « **Reply #11 on:** July 12, 2009, 03:47:45 PM »

FIRE LAPPING

Chas. · « **Reply #12 on:** July 12, 2009, 04:22:36 PM »

I had some problems with CCI primers that I bought about the time you were having that problem. Some wouldn't lite off at all and some wouldn't completely ignite the H4198. I also had squibs that I had to drive out.

And it seems like some other folks were having problems with CCI about then.

Smokin Joe · « **Reply #13 on:** July 12, 2009, 07:10:58 PM »

.455 sounds a little improbable. What did you measure the slug with?

StevenK11 · « **Reply #14 on:** July 13, 2009, 02:55:15 AM »

Quote from: smokinjoe5150 on July 12, 2009, 07:10:58 PM

.455 sounds a little improbable. What did you measure the slug with?

Digital calipers. Triple checked. Also, tested the calipers on a 45-70 cast bullet taken out of the box, and it measured .459, as it should.

I re-checked the measurements today and it is possible that the muzzle is .456 also. The digital display bounces between .4555 and .456. It doesn't resolve measurements well at the .0005 increments.

The breach was .456 though.

Fairshake · « **Reply #15 on:** July 13, 2009, 04:17:42 AM »

458 should do fine in 456 bore. That's with cast of course. The Lee sizer dies do work but the ring is of a small diameter. You might want to check out your forearm on that rifle. See if you have a serious fit problem. It it's touching in different places that rifle will never shoot. Had to take out some wood and use a plastic washer on mine so that it would pass the dollar bill test.

StevenK11 · « **Reply #16 on:** July 17, 2009, 04:56:12 AM »

I want to say first that I am thankful for all the help so far. You guys have given me some great information and ideas.

Second, I haven’t given this rifle a good test of loads (just finding this out now)! The 405 gr bullets that I had boxed up and haven’t been testing gave me a good surprise.

FYI: I was hell-bent on re-creating the classic 45-70 experience (45-70-405) two years ago, so I jumped right into 777 “blackpowder” loads, had some success with it, but moved so quickly into smokeless and 300gr loads without following through on testing the 405gr further.

Latest range results:

- Loads tested (5 shots per):
o   300 gr, resized and lubed .457 with that Lee resize kit
o   300 gr with the default .459 un-sized bullets; a reduced load though (one grain less Unique)
o   Pulled out my old box of 405 gr, dusted the box off, and loaded a set.

- At the range:
o Load still shot wide, close to 4”, but nothing resembling a group. No definable change from previous tests.
o   Second load shot a 2.5” group. Interesting…
o   Third load shot a 2” group, with three holes at 1”. One flier 4" away though.

I built a new set of loads to test some more (10 shots per):

-   Same 405 gr load; I want to verify the groups again on this one with a 10 shot set.
-   300 gr with 11 gr Unique. Reduced one grain further to see if improvement continues...

The load data I’m using comes straight from the GMDR.com Oregon Trail loads link on their site. When I used starting loads of slower burning powders, the performance dropped off, which is why I switched to faster burning powders. They do burn very clean, with no un-burnt powder in the barrel. Also, I do safety checks with a marked dowel rod in the cartridge to prevent double charges.

Weather has been bad today, so testing is going to be delayed…

Smokin Joe · « **Reply #17 on:** July 17, 2009, 05:47:12 AM »

Have you tried any SR-4759 loads? I have very good luck with just about any cast bullet using it. Burns clean; no filler needed.

StevenK11 · « **Reply #18 on:** July 17, 2009, 06:57:08 AM »

Quote from: smokinjoe5150 on July 17, 2009, 05:47:12 AM

Have you tried any SR-4759 loads? I have very good luck with just about any cast bullet using it. Burns clean; no filler needed.

I haven't, but have seen that powder show up often in forum comments on good 45-70 loads. Also see that it's right between Unique and IMR 3031 for powder burn rate. I know Unique/Universal are a little too fast a burn rate, but SR-4759 looks to be just right for what I'm trying to accomplish.

IMR description: This bulky powder really shines as a reduced load propellant for rifle cartridges. Its large grain size gives good loading density for reduced loads, enhancing velocity uniformity.

Lyman 49th edition has some good loads in the ~1200fps area for SR-4759. I'll have to pick up a pound and give it a try.

Thanks!

coues2506 · « **Reply #19 on:** July 17, 2009, 08:07:54 AM »

My BC shoots min of angle with 27gr. of SR4759 and the Remington 405 bulk jacketed soft point. 1300fps. I have a lot of H4831 to use up and I get 1350fps with 53gr and same bullet. Accuracy is in the 2 inch range. With any lead 405 I have to drop all the way down to 22gr. of H4198 to get MOA. and 1100fps. I really like the Rem 405 and they are cheap enough. Midwayusa.com has them. I have never had great luck with any lead slug over 1200 fps. Some say they do. My HandiRifle 45-70 loves the Rem 405 too. Never had a use for a light bullet in 45-70 - poor sectional density. The 405 will completly penetrate anything on this continent. The Speer 400 shoots just as well with the same loads but costs quite abit more.

quickdtoo · « **Reply #20 on:** July 17, 2009, 08:56:43 AM »

I've got 2 BCs, one is scoped and shoots jacketed bullets extremely well, the 350gr Hornady at 2050fps, the other has been rechambered to 45-120, it shoots the 405gr Rem at 1500fps into an 1½" at 100yds with the peep sight, and the 525gr BTB Piledriver at 1800fps, use the right sized cast bullets for the bore and they'll shoot good.

Tim

StevenK11 · « **Reply #21 on:** July 17, 2009, 10:08:41 AM »

Quote from: coues2506 on July 17, 2009, 08:07:54 AM

My BC shoots min of angle with 27gr. of SR4759 and the Remington 405 bulk jacketed soft point. 1300fps. I have a lot of H4831 to use up and I get 1350fps with 53gr and same bullet. Accuracy is in the 2 inch range. With any lead 405 I have to drop all the way down to 22gr. of H4198 to get MOA. and 1100fps. I really like the Rem 405 and they are cheap enough. Midwayusa.com has them. I have never had great luck with any lead slug over 1200 fps. Some say they do. My HandiRifle 45-70 loves the Rem 405 too. Never had a use for a light bullet in 45-70 - poor sectional density. The 405 will completly penetrate anything on this continent. The Speer 400 shoots just as well with the same loads but costs quite abit more.

That's what I'm seeing. As I approach 1100fps, the groups are getting tighter with the cast bullets I haven't shot jacketed, mainly due to the cost.

StevenK11 · « **Reply #22 on:** July 17, 2009, 10:11:42 AM »

Quote from: quickdtoo on July 17, 2009, 08:56:43 AM

I've got 2 BCs, one is scoped and shoots jacketed bullets extremely well, the 350gr Hornady at 2050fps, the other has been rechambered to 45-120, it shoots the 405gr Rem at 1500fps into an 1½" at 100yds with the peep sight, and the 525gr BTB Piledriver at 1800fps, use the right sized cast bullets for the bore and they'll shoot good.

Tim

Now, that's what I'm working towards.

While I might be able to coax the light 300grs to shoot a little better, it's the 405 where I'm having the better luck.

tykempster · « **Reply #23 on:** July 19, 2009, 12:49:09 PM »

You could try Trailboss powder too.

mechanic · « **Reply #24 on:** July 19, 2009, 02:58:33 PM »

Your Varget load listed with the 405 gr. is my favorite load, except I use a hollow base bullet. I get MOA or very close to it consistently with this load and without a sore shoulder. My BC did not really begin to shoot well until I relieved the forestock and lapped the barrel a bit. With the bore shiny accuracy improved by half or more.

PawPaw · « **Reply #25 on:** July 19, 2009, 04:27:24 PM »

If you're using black or substitutes, one of the tricks we've learned is to put a grease cookie under the bullet. Including a grease cookie under the bullet cut my group sizes in half.

Junior does an article on the process here. http://www.castbullet.com/shooting/1871.htm

45-70.gov · « **Reply #26 on:** July 19, 2009, 04:46:01 PM »

i just pushed a slug through my 45 70
it is much tighter at the breach than the mussel

though i didnt measure it

StevenK11 · « **Reply #27 on:** July 25, 2009, 03:29:42 AM »

This is an improvement from what I previously have shot with this rifle.

It's a light load: 11gr Universal, 300gr laser cast RNFP, shot at 100 yards.

One thing that does happen often is that the first or second shot is always separate from the following group. I suspect it is because I don't run a dry patch through my barrel before I start shooting. The last patch was an oiled patch. It's what I do before I put the rifle away after cleaning. Time and time again, I forget to wipe that out before heading to the range.

quickdtoo · « **Reply #28 on:** July 25, 2009, 09:51:42 AM »

Keep workin with it, you'll git er!!

Tim

sr sawyer · « **Reply #29 on:** July 25, 2009, 01:56:35 PM »

After cleaning most barrels require two or three rounds to foul the bore again. It is common for the first couple to be away from the following group.

In my experience the first couple of shots are generally higher than subsequent ones just as your target shows. Don't clean mine after every outing unless I shoot a lot or they get wet because cleaning too often can be worse than not cleaning often enough IMO.