Drop Tube Test: Maximum BP Charge 45-70

[M71]

Just to appease my never ending curiosity I decided to see how much black powder I could effectively get into a 45-70 case and still be able to place a .030 Walters wad over the charge without spilling any using my homemade copper drop tube. Well, the maximum I could fit was 75 grains of Goex FFg. How does this result compare with your drop tube? I charged 5 rounds using Paper Patched 530 gr. bullets. Needless to say there was a considerable amount of force needed to compress this charge. If my short throated 1874 had adequate freebore less compression would be necessary because I wouldn't have to seat the bullet so deep. My compression depth measured from the mouth of the case to the wad is .572. I'm going to discuss adding some freebore to my chamber with my gunsmith to facilitate longer COAL for PP bullets. The maximum allowable COAL with the 530 gr. bullet is 2.915. What are your thoughts? I'm going to test these rounds for accuracy at 100 yards and document the velocity increase over my standard target load of 68 grains. I'm familiarizing myself with this rifle as a stock 45-70, but originally was going to punch it out to 45-90. I'm having second thoughts about that now. For some reason I can detect the felt recoil increase using 70 grains over just 2 grains back at 68. I'm sure these 75 gr. loads will get my attention even with my weight added 14 lb rifle. Everyone has an opinion, let's hear yours.

[Jim2]

does your OAL engage the bullet into the leade or does it allow for some movement before engaging?

Jim

[montana_charlie]

In an earlier thread about your newly-acquired Pedersoli Long Range you said this:


Now comparing the new "Long Range" 1874 and my old "Super Match" Roller there is a significant difference in the throat or "leade" dimensions. My currently loaded paper patched and grease groove bullets for the roller will not fully chamber in the new 1874. The measurement between the end of the case mouth and where the land starts is much much closer than the older roller. Free bore has been reduced to almost zip. I prefer PP bullets so I'm going to seat the bullet more to compensate.

The chamber in your Pedersoli Sharps looks like this:

http://i684.photobucket.com/albums/vv203/montana_charlie/45-70_Govt__PedersoliwithPGTBullet.gif


As you can see, there is almost a quarter inch of freebore between the chamber mouth and the start of the leade. If you count the chamber transition angle (the 'step') as part of the freebore, the total length is .333".

That length of freebore is what allows the PGT bullet (also pictured) to set out of the case far enough to expose one and a half grease grooves.

If you are convinced that you have 'no freebore', do a chamber cast.
It should have been one of your first actions, anyway.

If cases fired in your roller won't chamber in your Sharps, check out how 'fat' they are.


Are your patched bullets bore diameter ... or groove?

[M71]

It takes just minimal pressure to fully chamber a round. I can't lengthen COAL without hard resistance.

[Gunlaker]

You must be using a groove diameter patched bullet I guess. I don't know how much plain Goex FFg I can put into my .45-70 cases as I don't use it much. I drop tube 82gr of FFg Express, or the same amount of Swiss 1.5 into my cases with room for a 0.030" veg wad and 0.060" LDPE wad. It requires only small amount of compression to push the wad down far enough to seat my bore diameter PP bullets just over a tenth of an inch into the case. Both of those powders are more dense than plain Goex FFg though.

Chris.

[M71]

Charlie, The lands start about 40 thousands ahead of the case mouth. I'm only getting to seat the bullet out as far as it is because it's a tapered bullet. I don't think my chamber dimensions match the diagram. I'll make a chamber casting to verify. Thank you, Bruce

[Knarley]

I myself was amazed at the difference that just changing brands of powder made. Graf & Sons takes a lot less room as does GOEX, if weighed.
I was having problems with some of my rounds chambering, and was looking at the wrong end of the round. After full length sizing, they fit fine. As Montana Charlie mentioned, they might be a tad "Fat".

Knarley

[M71]

Knarly, Your right, the fire former cases from the roller were "fat". I ran the finished rounds into the full sizing die without the stem just enough so they would chamber.
Yes, the PP bullet is groove size with the patch.

[M71]

The lands start real close to the end of the case mouth.

[Red River Rick]

M71:

Buy this mould and all your troubles will go away:http://www.dixiegunworks.com/product_info.php?cPath=22_101_283&products_id=8051

RRR

[Knarley]

You have to remember, putting 5 gallons into a 3 gallon bucket don't work. ( I told my boss that once, he weren't pleased.)
I'm thinkin' regardless of where the lands start, you aren't gonna get that much more powder in the case. They might be bulging because of that now.........
I believe that the case, as a "Government", was 62-63 grains any way.....

Knarley

[kokomokid]

Gunlaker; How are you getting the bullet to stay in the case? Can you pick up a loaded round by the bullet? I use about the same load with 82 grs of 1 1/2 swiss and almost no compression.

[Skank Killer]

M71, if it were my rifle, I think I'd get a good BPCR gunsmith to go ahead and punch that chamber out to 2.4" and go from there. It's my intuition that the 45-70 is just too short to take full advantage of the benefits of paper patching. See about having the chamber cut with the proper leade and a bit of freebore, then knock yourself out. I bet you'll get better accuracy by pushing your 530-540 grain bullets with 85-95 grains of powder, rather than the current limitations imposed by the short case.

[Gunlaker]

Kokomokid, my paper patched rifles have the chamber cut to .474" diameter at the outside of the case mouth. My bullets are patched to about .451" so are a nice slip fit into the case. They are not in there so tight that you'd want to carry them around for hunting, but they stay in the case for target shooting.

Chris.

[Gunlaker]

Skank Killer, have you seen what Brent Danielson ( and others with the same chamber ) are doing with the .45-70 in NRA long range matches? Brent seems to really have this figured out.

My .45-90 has shot better than my .45-70 now, but it took a while to get there. With a 535gr bullet moving at 1365 fps the rifle is very unforgiving if you have any inconsistency in holding though. The .45-70 may choose to be a smarter play.

Chris.

[M71]

This is my preferred seating depth. I really like shooting paper patched bullets over GG. Perhaps I could take these rounds to my gunsmith and have him duplicate my new chamber to accept these "Long Ones".

[Don McDowell]

Adding freebore will make matters worse for paper patching. Learning to use what the rifle will shoot well, and not what you think it should shoot well.

[Don McDowell]

I myself was amazed at the difference that just changing brands of powder made. Graf & Sons takes a lot less room as does GOEX, if weighed.

Knarley

Take some of that Grafs powder and pour it out on a sheet of paper, and take some Goex 2f and pour it on beside the Grafs, right away you should see the difference in kernel size. The 2f Schuetzen and Swiss is about the same size as Goex 3f.

[Knarley]

Take some of that Grafs powder and pour it out on a sheet of paper, and take some Goex 2f and pour it on beside the Grafs, right away you should see the difference in kernel size. The 2f Schuetzen and Swiss is about the same size as Goex 3f.

So the idea of standardization is out the window. I always figured that FFG was FFG. Yes I HAVE noticed that. A guy learns something here every day. I have wondered how some people get SO much powder in a 45-70 case, now it starts to make sense. Until just as of late, getting any thing other than GOEX around here wasn't going to happen. Happily that has changed a bit. As far as getting the others, it's at least 100 miles.......... one way.
( Bucket list)

Knarley

[Gunlaker]

Knarley just to confuse things even more, if you try the new Goex Olde Eynsford it'll go the other way. It's the lightest fluffiest powder I've used. Measured by weight it gives nearly the velocity of FFFg.

The stuff can also vary quite a bit from lot to lot as well.

Chris.

[M71]

Adding freebore will make matters worse for paper patching. Learning to use what the rifle will shoot well, and not what you think it should shoot well.

Excellent point Don, well taken. I assembled 50 fresh ones and will be testing them on the next reasonably cool day. I've been recording the settings on the Vernier sight. With my loads, 23 Points is 50 yards, 31 Points for 100 yards and so on. I'm learning as I go. Are the settings linear? For example, would another 8 Points (39) be approximately for 150 yards and another 8 (47) would be for 200 yards? Knowing what to expect could save some time and $$. There may very well be too many variables to predict settings. I changed out my standard front sight with a taller one because it's lowest sight setting was 8" high at 100 yards. The new micrometer bubble level sight is a big improvement. I'll post my last 100 yard target, all shots are shown including pre sight adjustment. It was extremely hot out, I got cooked.

[Don McDowell]

M71 you'll have to try those loads if they group well at various distances and see. While figuring 16 minutes per 100 yds is a decent base line. It doesn't always hold true, even you you're not dealing with tailwinds, quartering headwinds, mirage or changing light..

[montana_charlie]

With my loads, 23 Points is 50 yards, 31 Points for 100 yards and so on. I'm learning as I go. Are the settings linear? For example, would another 8 Points (39) be approximately for 150 yards and another 8 (47) would be for 200 yards? Knowing what to expect could save some time and $$. There may very well be too many variables to predict settings.
When you know your sight setting for 100 yards and for 200 yards, I have a quickie little Excel tool that will give you estimates out to 1000 yards.
It isn't perfect, and it is limited to the characteristics of a single load. But because it uses your sight settings, the estimates are unique to your rifle.

PM me an email address and I will send it to you.

CM

[Don McDowell]

Knarley just to confuse things even more, if you try the new Goex Olde Eynsford it'll go the other way. It's the lightest fluffiest powder I've used. Measured by weight it gives nearly the velocity of FFFg.

The stuff can also vary quite a bit from lot to lot as well.

Chris.

Chris? How many lots of OE have you had? I've had several since that very first lot, and the 2 f seems to be especially consistant. The 1.5 hasn't shown me anything that would be cause for concern yet.

[BrentD]

M71, if it were my rifle, I think I'd get a good BPCR gunsmith to go ahead and punch that chamber out to 2.4" and go from there. It's my intuition that the 45-70 is just too short to take full advantage of the benefits of paper patching. See about having the chamber cut with the proper leade and a bit of freebore, then knock yourself out. I bet you'll get better accuracy by pushing your 530-540 grain bullets with 85-95 grains of powder, rather than the current limitations imposed by the short case.

Fwiw, I push a 537 gr bullet with 82 gr of Swiss 1.5 fg powder out to 1000 yds with superb accuracy. With a 45-90, I need to use a minimum of 102 hr of the sam, and that is too much.

There is no value in a 90 or longer unless you are loading hunting ammo, and even that is debatable.

You guys should all be in Raton right now for the Nationals. Awesome weather, geography, food, weather (did I mention the incredible weather?), and of course, shooting.

[Gunlaker]

Don, I wrote that poorly. I'm meant to say that in general black powder density can vary from lot to lot. I didn't mean that OE can vary a lot. I'm still on my first case of OE 1.5, so only one lot of that stuff. It seems to be working well in my .40-65. It shot quite consistently in Kamloops for our recent silhouette match so I'm still happy with it.

Chris.

[Gunlaker]

Brent what are the temperatures like down there? Hot enough to fry a Canadian? :-)

Chris.

[Don McDowell]

Oh ok, my bad Chris. I know the old Goex could be pretty irratic from one batch to the next, and Elephant wasn't the best of consistency either...

[BrentD]

Chris, everyone was wearing jackets yesterday. It was almost cold. Mostly it's been in the 70s and low 80s.

[sharpsguy]

M71--Don't screw up the chamber on that rifle. It will shoot paper patch just fine with 70-72 grains of 2f black powder if you load it correctly. You just need to find the right bullet.

[Chill Wills]

OT - Brent mentioned Raton NM

I am packing the vehicle and will be there this afternoon sometime.
If any of you, old friends and new, will be there this week, Please come by and say Hello!
Woody and I will be in Space 116 and often like to sit outside and have a beverage most anytime after the days match is over.
Michael Rix

(Keeping a chair in the vehicle insures you always have a place to sit.)

[semtav]

M71
Since you asked for opinions, I'll give you mine.
If you want to use what you have (bullet) in what you have (gun) the only thing you have to do is find the right powder to make it work.

Since you have what you have, just find what powder it will work with.
And don't rule out BH209 unless you are shooting NRA matches, or FFFG for that matter.

I was fortunate enough to buy a PJ PP mould from Dan T before his passing. It is .454 dia and I patch to Groove dia and I have been able to make it work in every 45 cal gun I own with very good accuracy. that includes rifles with freebore, and rifles with chambers like yours by using the right powder.

I shoot BH209 in my 45-70 but Im sure you could make fffg perform the same. The one thing I did with the Groove dia bullet is go to a lot harder alloy. 12.5-1 wth BP and an antimony alloy for the BH209, but all are slip fit.


Your tapered bullet should be able to do the same.

[kokomokid]

How are is the bear issue this year? LB

[BrentD]

No bears. Way too green. It's like Iowa out here.

[Don McDowell]

M71, I was looking at your groups those don't look bad, you might want to check your fouling control. Also you may want to give some consideration to a different front sight. If you're already at .47 to make a 200 yd setting , you'll likely have to use add on comb riser to keep a consistant cheek weld when you get out to 600 and beyond. Most of our( my wife's and my) rifles only use a setting around .30 at 200 yds.
Also might want to get some regular targets to shoot, the tan colored background is easier on the eye than the bright white.

[Don McDowell]

OT - Brent mentioned Raton NM

I am packing the vehicle and will be there this afternoon sometime.
If any of you, old friends and new, will be there this week, Please come by and say Hello!
Woody and I will be in Space 116 and often like to sit outside and have a beverage most anytime after the days match is over.
Michael Rix

(Keeping a chair in the vehicle insures you always have a place to sit.)

You guys hold hard and squeeze center. If Cody didn't forget to pack them he's got a package of the KAL bullets for that Dan T 90 chamber. I had a few of the wrapped, to give you at Cheyenne, but by the time the box fell out of the pickup a half dozen times, the paper don't look so hot.. See you in August.

[Gunlaker]

Brent those are my favorite temperatures :-). I just assumed that it would be very hot. At some point I'd like to shoot the bptr matches there.

Chris.

[BrentD]

We are at 6k ft plus a bit, so nor so bad, but it can be.

Better bring lots of bug dope to sit out with beers

[BrentD]

We are at 6k ft plus a bit, so nor so bad, but it can be.

Better bring lots of bug dope to sit out with beers

[MT Chambers]

Up here in Canada each 45/70 brass has diff. capacity, Winchester holds alot more powder then Remington cases, not sure about Fed, Starline, etc.