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geargnasher
11-24-2010, 03:32 PM
Continuing with the Shiloh Sharps experiment, I have some questions for the big-bore, straighwall shooters, and I apologize in advance that this will be long-winded.

I'm doing all my initial loading and shooting experimentation with smokeless powder and that seems to be playing hoc with boolit design, particularly with lube groove designs of the available heavyweight boolits. It seemst that the deep, square grooves of the Lyman 505 and 535 moulds hold too much lube for smokeless powder and 100-yard accuracy is less than good (4-6"). I've tried lubing as few as two grooves with Felix lube and I see some improvement, but recovered boolits still have big chunks of lube left in the grooves in places. The gun has a 1:20" twist as best I can measure it, and I've been using IMR 4198 in the 38-42 grain range with 1 to 1.5 grains of Dacron. I tried some of the 505 grainers without Dacron and the groups literally doubled, not sure if the lube was still holding to the boolits or not as I did get a lube star without filler.

I also tried Lee's 400 grain roundnose flat point, but they cast undersize and I got a considerable bit of leading and 8" groups at 100 yards for several five-shot strings. Here, I don't know if the gun doesn't like the lighter boolit or if I was in the wrong velocity range for best accuracy with it, or if the leading was the whole problem. My main reason for trying the lighter Lee boolit is the skimpy lube grooves, hoping to eliminate the lube-retention problem of the bigger, BP boolits.

Last night I cast up some Lee 450-grain RFN boolits and verified the nose is correctly sized for the bore, and the driving bands actually cast at .4595" which I figure is just right for my .4582" groove, and the lube grooves are shallow and seem to be more suited to smokeless, we'll see.

The questions I have are are any of you having luck shooting BP boolits with smokeless lube and powder? If so, what velocity ranges and powders are you using? Is it your exprience that these guns like heavier boolits in general, or lighter ones? According to the Lyman data I have, I've been shooting in the 15-1600 fps range, but I don't know what the real-world best accuracy range is for this caliber.

Oh, and any of you who think that 30 grains of 4198 behind a 400-grain boolit in a 45/70 kicks hard, you ought to come shoot this thing with 42 grains and a 535-grain boolit!

Gear

montana_charlie
11-24-2010, 07:03 PM
I know the current Shiloh .45 caliber barrels have a 1 in 18 twist. I think Shilohs have always had that twist rate, but I could be wrong.

The 'fast' twist sorta calls out for long bullets. The government bullet, as well as the Creedmoors and Postells have always performed well in Shiloh guns. And, that pretty well covers the mechanics of which bullets work with the way the barrel is cut.

As for performance when SP is the propellant, that's something I have no information for.
But, I would probably be inclined to use 'soft' (BP type) lube on the bullet.

CM

6.5 mike
11-24-2010, 09:11 PM
Thought I was the only one who's 405 gr lee drops small, but just right to paperpatch. BTW Gear, your "rules for precision" is also the true meaning of the term "close enough for goverment work", only thing I remember from a $80,000.00 avaition school [smilie=l:.

geargnasher
11-24-2010, 11:24 PM
Thanks, MC, good info. Might try softer lube with the heavies.

Gear

MGySgt
11-25-2010, 01:47 PM
FWIW

I shoot 2 different 45/90's - both with smokeless.

Lube = Lyman Moly
Powder = 3031
Wt = 41.5 - 43.0
Dacron filler to fill in the airspace.

Boolits = 430gr MM LARGE FP, 450gr MM with a smaller meplate. Both in WW

Both shoot MOA

Rifles:

IAB 1866 repro of a Sharps Businees rifle. Bore size = 461, size to 462.
Pedersoli Quigley Bore size = 459 sized to 462 (same sizer die and boolits)

The IAB started as a 45/70 but due to a long chamber, had it rechambered to 45/90.

The IAB has taken 2 elk - both cows, about 150 yards each, SOLE Mid Range rear and Globe Front.

When I fire them on the range I use a Circle in the front globe so it is a Circle in a Circle and the bulls eye is in the center - Real accurate!

That is what works for me.

Drew

94Doug
11-25-2010, 02:04 PM
I don't know if I qualify, but in shooting the .458 Lott, I use 3031 in most of my loading. I had luck with 4759 and Trail Boss as well. My main goal however, was to NOT use any fillers. I can't say I have watched to closely for accuracy either. Let me know if there are any designs you might want to try out. I could possibly cast up a few for you.

Doug

geargnasher
11-26-2010, 12:04 AM
Again, thanks for the input, seems there aren't many people shooting smokeless in the 45/90 these days. How does the 3031 burn? I usually try for the slowest powder I can get to burn cleanly and match the barrel length for the pressure range I'm using when working up cast boolit loads, but the straight wall case can be a detriment to good ignition without sufficient cast neck tension etc. I was really tempted to try Winchester 748 but haven't seen any data out there, figured I'd do some interpolation and try it out if I can't get happy with 4198.

This gun has already taught me how much I don't know about artillery!

This morning I decided to get the neighbors out of bed with several strings of the 450-grain Lee boolits, sized .0005" over groove diameter and stuffed on top of one grain of Dacron and 36 grains of 4198, shot a 1/4" 5-shot string at 25 yards and a 1" 5-shot group at 50 yards with much milder recoil. I didn't quite get all the leading out from the last round of shooting, and had a bunch more on top of it in the same place about a foot back from the muzzle. If I can get this thing really clean and grouping well at longer range, I just might have it licked. IF.

Gear

MGySgt
11-26-2010, 10:30 AM
3031 burns fine for me.

I normaly clean the rifle with a bore snake.

If I see leading, I use a brass brush with Chore Boy Copper pad (stipped down to individual strands) wrapped around it fo a tight fit. Lead doesn't stand a chance. 4 or 5 pass throughs and the lead is gone!

The longer I shoot them from a Clean to the steel, the better they shoot. I do not normally use any bore solvent in them.

Run the bore snake through a few times, wipe it down and set it back in the safe.

excess650
11-26-2010, 10:51 AM
You might want to try AA5744, SR4759, or even Unique with 400ish gr bullets. Better yet is a compressed load of BP lit off with RP 2-1/2 primers. Pan lube or lube in an oversize die and shoot as large diameter as will chamber easily. Soft lubes may well work better in that relatively slow twist with smokeless(alox/beeswax). Marlin LAs and Ruger SSs are the same or similar twist in 45-70, so finding a decent load shouldn't be too problematic.

geargnasher
11-26-2010, 12:24 PM
I prefer 2400 for most of my 45/70 stuff with either 340 or 400-grain Lee boolits, but even LLA will work for lubing those. I was trying for a bit more velocity for shooting out to 500 yards without running out of tang sight elevation adjustment :-D

I'm cleaning this thing up right now with the FO-II, I'm going to tumble-lube and then fill the grooves with Felix lube, see if that helps.

Gear

geargnasher
11-26-2010, 12:40 PM
3031 burns fine for me.

I normaly clean the rifle with a bore snake.

If I see leading, I use a brass brush with Chore Boy Copper pad (stipped down to individual strands) wrapped around it fo a tight fit. Lead doesn't stand a chance. 4 or 5 pass throughs and the lead is gone!

The longer I shoot them from a Clean to the steel, the better they shoot. I do not normally use any bore solvent in them.

Run the bore snake through a few times, wipe it down and set it back in the safe.

I've worked this leading patch over using the usual suspects, a very tight Chore-Boy-wrapped 45-caliber bronze chamber brush, then followed with tight patches, about 100 strokes more and the patches are still pushing out flakes, so I went with the steel wool wrapping on a different bronze brush, put about 50 strokes through it and am still getting flakes and slivers out with a tight patch. That's the point I give up and degrease the thing and let the electrons do the work. This gun has never fired copper, and I cleaned it quite well before shooting and never saw or felt any pitting or rough spots in the bore. The .457" boolits ate my lunch. "Swell up to fit the bore" my a$$. Maybe with BP and pure lead, but I think the round of 400-grainers I tried lost all their lube out the muzzle before they ever obturated.

I generally never clean my rifle barrels except to run a dry patch through them after shooting, it seems they get a nice patina from the carnauba wax I add to Felix lube and shoot more consistently without cleaning. I say generally because I've had some trouble with the last batch of lube attracting moisture, but it's an altered recipe using a different stearate, testing this hygroscopic effect is an ongoing side experiment. I only clean to metal if I get leading, and that doen't happen to me very often any more.

Gear

94Doug
11-26-2010, 01:43 PM
I have had a few 3031 loads that were either too light, or powder that was too old that failed liftoff. The boolit only went down a few inches, and the powder was everywhere when the action opened. I think I was trying 50 grains with a light boolit. I am out of the old powder, and generally use loads from 55-60 grains, so haven't had that problem again.

Doug

excess650
11-26-2010, 01:48 PM
Do you have any GCed boolits to load? A few moderate velocity rounds may scrape the remainder of your problem out.

Like you, I don't clean any more often than I deem necessary. My 30-06s, 7.5x55s, 357 carbines, 45-70s, 30-30s, 35 Rem and 38-55 might get a Hoppes patch on occasion, but not more unless I know that I've exceeded the limits of my alloy and lube. I forgot the 8mm with rough bore!:holysheep

montana_charlie
11-26-2010, 02:24 PM
The .457" boolits ate my lunch. "Swell up to fit the bore" my a$$. Maybe with BP and pure lead,
Some people say they know how much, and when, a 'lead' bullet gets bumped up by a smokeless load. But, I don't think they really, really, know.

If you actually need a bullet to bump up, I would only trust BP to do it.
I believe it gets bumped to fully fit the chamber before it even gets out of the case.

CM

MGySgt
11-26-2010, 03:33 PM
Over the years I have had some badly leaded barrels, the Chore Boy wrapped bore brush (I only use 50 cal ones) never failed to remove them. Sometimes 10 push throughs and sometimes double that.

Word of caution on carnubba wax. On a wet day it will trap moisture between it and the barrell. I don't use it anymore.

Like CM I don't think that smokeless can bump a boolit up. Differnet peak power range.

Bullshop
11-26-2010, 03:58 PM
Smokeless can, does , and will bump up a bullet or boolit. The slower burning smokeless powders will bump even a hard bullet it just happens more slowly that with BP.
You can use faster smokeless powders to bump more quickly and perform like black powder.
In my experiance that burn rate ends at about the burn rate of 2400.
Its pretty easy to prove this out by shooting bore diameter boolits either PP or GG.
If you start with a powder that is too slow to bump and progressively keep going to faster powder you will see that until you reach a minimum burn rate accuracy will be terrible and when you reach that minimum it will improve. If shooting PP with this test before the minimum is reached the patch will often be blown off. This will not do good things for your barrel but it will prove that smokeless will bump up. This same thing takes place any time a bore diameter conicle boolit is fired from a ML using a BP sub. A BP sub is just another smokless powder with a fast burn rate.
Another proof that even slow smokeless will bump even a hard bullet can be seen in some of the factory ammo that uses two diameter bullets. The two diameter bullets are what you would get if you order some bulk bullets from Rem or Win. The forward portion of these bullets are bore diameter while the rear is groove.
If you were to recover some of these two diameter bullets you will see that the forward portion of the bullets that started out at bore diameter is now fully engraved by the rifling and is now groove diameter where it fill to the barrel groove bottoms.

405
11-26-2010, 07:25 PM
gear,
Since you're well into the experimentation stage and if you want to see how well the gun can shoot with cast and smokeless you might try a gas-checked bullet right at or .001 larger than groove diameter. I didn't say how fast- this is all about accuracy and keeping the pressures in the Sharps at safe levels and the recoil mild.

Get a few of the "standard GG GC" 400-425 gr. bullets sized to .458" or .459". Use a medium alloy with a BHN of about 12-15. Lube with a fairly soft lube like SPG or Felix. Use an M die or similar to ease bullet seating. Don't crimp other that to take the "bell" out. Load with standard large rifle primer like the Rem 9 1/2. Load with about 25 gr of 5744 and top with a VERY fluffy, low density filler like dacron. Fill the space between powder and bullet base with the filler. It should only take about a .75gr +/- weight of dacron teased out to fill the case. Seat the bullet so the front drive band touches the rifling. The RCBS 45-405-FN GC bullet is ideal for this. It should shoot well out to at least 300 yards.

This load or similar shoots extremely well in my Shiloh Sharps 45-70 and my C Sharps 45-110 and does not lead!. Since the 45-90 is in between no reason it won't work. Might as well see HOW accurate the Shiloh can be. Also, my thought is that it may be an uphill battle trying to use a plain base bullet on top of smokeless. Except at very, very low velocities and pressures you might have to use an extremely hard alloy and even then I'm not at all sure of the outcome- either for accuracy or leading.

geargnasher
11-26-2010, 11:34 PM
gear,
Since you're well into the experimentation stage and if you want to see how well the gun can shoot with cast and smokeless you might try a gas-checked bullet right at or .001 larger than groove diameter. I didn't say how fast- this is all about accuracy and keeping the pressures in the Sharps at safe levels and the recoil mild.

Get a few of the "standard GG GC" 400-425 gr. bullets sized to .458" or .459". Use a medium alloy with a BHN of about 12-15. Check. Shooting ACWW+1% Sn at 12.5 bhn sized .4592" after honing the H die. Lube with a fairly soft lube like SPG or Felix. Felix lube according to Wiljen's recipe. Use an M die or similar to ease bullet seating. Using Lyman .45 "M" die, only sizing the case far enough into the sizing die to get the "neck" ID to .003" under sized boolit diameter, so the expander is mostly just bellmouthing the case.Don't crimp other that to take the "bell" out. Check. Load with standard large rifle primer like the Rem 9 1/2. Using Federal 215 per another member's recommendations, I've never used a cleaner-burning primer. Load with about 25 gr of 5744 Lyman #49 favors that one, but I can't readily get AA powders here. and top with a VERY fluffy, low density filler like dacron. Fill the space between powder and bullet base with the filler. It should only take about a .75gr +/- weight of dacron teased out to fill the case. Precisely. I only tried NOT using Dacron twice, never again with this cartridge. Seat the bullet so the front drive band touches the rifling. Check. The RCBS 45-405-FN GC bullet is ideal for this. It should shoot well out to at least 300 yards. The only mould I have out of five that fits the gun is the Lee 450-grain bore-rider, both the nose and the bands fit the bore/groove to a tee.

This load or similar shoots extremely well in my Shiloh Sharps 45-70 and my C Sharps 45-110 and does not lead!. Since the 45-90 is in between no reason it won't work. Might as well see HOW accurate the Shiloh can be. Also, my thought is that it may be an uphill battle trying to use a plain base bullet on top of smokeless. Except at very, very low velocities and pressures you might have to use an extremely hard alloy and even then I'm not at all sure of the outcome- either for accuracy or leading.

Recommendations for GC boolits duly noted, but I don't have any moulds or checks right now. I'll have to work with what I have, but I doubt I'm exceeding the capability of PB boolits here, I believe my problem with leading up until now has been shooting boolits at or .001" UNDER the largest groove dimension. I say largest because the grooves don't make a true circle, they are actually shallower in the middle than at the edges of the cuts. A measurement taken straight across the grooves on a slug comes out .4575", but if the slug is rotated to measure the edges, it measures .4583" or so. I was hoping that .457-8" boolits would seal, but no dice. I've pushed 12-13 bhn PB boolits to well over 1600 fps in other calibers with no trouble, the key is getting the right fit and soft launch. I'd really love to use H1000 or Retumbo in this cartridge but I'd never get them lit.

I spent three hours cleaning the gun and finally got all the lead out, then loaded up some more of the Lee 450 grainers with 42 grains of 3031 with .08 grain Dacron, also with 36 grains 4198 with 1 grain Dacron, shot 10 of each and maintained an 1-1/4" at 50 yards with both powders and identical POI. Back home and found only one small streak of lead in one groove and on one land near the end of the barrel. A few quick swipes with the Chore Boy and they were gone. That's the kind of leading I'm used to dealing with, I still don't know what the heck happened to get that stuff so stuck on before.

The game will be afoot in the morning, loaded up 30 more of the 3031 loads and 20 of the 4831, this time I tumble-lubed in 45-45-10 and then filled the grooves with Felix lube in the sizer. My local shooting range is having a qualifying event from 100-500 yards under very close supervision of the owner and staff and my FIL wants the qualification. Due to the location and layout of the range only "qualified" members who demonstrate competence/safety/capability during one of these events will be allowed to use the long ranges, and only using the gun with which they qualified. Wish us luck!

Gear

geargnasher
11-26-2010, 11:49 PM
I have had a few 3031 loads that were either too light, or powder that was too old that failed liftoff. The boolit only went down a few inches, and the powder was everywhere when the action opened. I think I was trying 50 grains with a light boolit. I am out of the old powder, and generally use loads from 55-60 grains, so haven't had that problem again.

Doug

What primer were you using? I used some IMR 3031 that I bought in 1990 for my first 30-30, it has not been stored under the best of conditions but smells and looks fresh. Not pungent, just fresh. I also used Dacron filler and magnum primers, seated to engrave hard, and plenty of neck tension from un-annealed necks. The powder had no choice but to light, even at 42 grains.

Gear

405
11-27-2010, 09:59 AM
gear,
I hear ya on not having the mold for the GC bullet. And while 5744 is common I guess it's not everywhere. A very similar powder is 4759. You'll see it listed in various manuals. When using 4759 I reduce the charge a grain or two compared to 5744 because 4759 is a small tad faster.

I still think for your purposes the GC bullet is the way to go for smokeless. So in the future you might have to "bite the bullet" and get a GC mold or just purchase a 100 or so to see how they work. I shot the RCBS 405 GC a lot out of my guns with excellent results. But for longer range and just to experiment I designed three heavier GC bullets with better ballistic coefficients using Mountain Molds. So now have a battery of MM GC molds that work for any purpose in the Sharps with smokeless.... 420 gr, 460 gr and 520 gr. For BP in the same guns I shoot paper patched.

Oh almost forgot. I see that your M die sizes .003 under. That is a lot! May be needed for slower powders but for the type loads we're talking you don't need that much tension. Two things. If you have shot that brass a few times the necks are probably getting hard. Consider annealing them. With the plain based, fairly soft bullets... seating them into .003 undersize necks likely will swage them down at least another .001. So you may be shooting an even more undersized bullet. Consider getting a neck expander that will size the neck to only about .001 under bullet diameter. Might call Buffalo Arms to see what they have. Of course a GC bullet will not be affected by the swaging as it is seated into the neck. The GC "paves the way" as it is seated.

geargnasher
11-27-2010, 11:41 PM
Ok, the results are in, and I'll definetely be taking a different tack here. Groups were suprisingly (to me, anyway) good, maintaining 1.5" at 100 yards and 3.5" at 200. 300 things fell apart, getting minute of target paper and several 5-shot strings as good as 10", some worse. The problem is leading. TERRIBLE leading, the worst I have ever seen in any gun, and I thought I had it bad when I first started shooting cast years ago. I ran a dry patch through after 15 shots to check bore condition after getting a flier at 200 and pushed out, literally, chunks of lead. Ran the Chore-Boy through it a few times and it came out looking like it had been dunked in the lead pot, actually clogged and packed solid with lead and powder fouling. I rinsed and recleaned the bore every five shots after that, and I think finally the hard lead buildup that we couldn't get out at the range began to eat away the groups, as we tried the last five at 100 again and shot 6".

After this leading fiasco I think I'll have to break down and buy a GC mould, probably in the 500 grain range. The other option is to size down and paper patch something that I already have, but paper patching in any quantity is something I'm saving for my old age, when hopefully I have more time and higher ambitions. Of course I probably won't be able to do the .30-caliber ones then, but who knows. I really wish I could get to the bottom of the leading issue, because there is something terribly wrong and I need to learn what it is. Perhaps I'm pushing these PB boolits too hard after all, just seems crazy that I can shoot PB boolits at nearly twice the pressure in a .44 Magnum revolver with and have only a slight wash that never accumulates beyond the amount from the second shot, even three or four boxes into a session, and this Sharps leads with everything I've tried so far.

As for the M die, it might be a bit small, but between the advice I've gotten from Starline, some posts on this forum, a couple of different reloading books, etc. I was under the impression that neck tension was paramount to a good burn with 4198 and slower powders. I'm actually only partially sizing the brass so the neck is about the same ID as the expander spud's OD, so I could size less and still get consistent tension all the way down to zero if I wanted to. Starline says don't anneal unless using black powder, then annealing the necks is an absolute must. I have pulled boolits and checked for swaging on several occasions, I can't tell that any swaging is happening at all, or if it is only one or two ten-thousandths. I am not crimping at all, just straightening the bellmouth enough with the crimp die to chamber freely. But it isn't working, and I'm certainly keeping an open mind.

Again, thanks for all the input, please keep it coming!

Gear

MGySgt
11-28-2010, 07:52 AM
Starline and Annealing - I don't really care what Starline says. I anneal mine straight out of the box - new, and after 10 loadings.

Accuracy is soooooooooo much better with annealed brass.

I do use Gas Checked boolits.

Bass Ackward
11-28-2010, 09:31 AM
I'd really love to use H1000 or Retumbo in this cartridge but I'd never get them lit.

Gear


Wish an acquaintance were still alive. He duplexed. Used pistol primers and 7 grains of 2400 as a kicker with something else that he filled the case with that I can't remember. This was back before H-1000 or Retumbo though.

ricksplace
11-28-2010, 10:01 AM
I have never owned a 45-90, but I do cast for and shoot a 458 win mag. The case capacity of the 458 win and the 45-90 are pretty much the same. (I call my 458 a 45-90 belted express). I have had poor results shooting pb boolits, and excellent results with gas checks. For heavy loads, I shoot a 500 gr lee fngc with 65 gr of Nobel 104 (like 4350 -I have 10 lbs of the stuff). Have not chronod it yet, but I'm expecting about 1700-1800 fps with very low pressure and no leading. Recoil is stout but manageable. Great fun to shoot. When I worked up the load with the slow burning powder, the cases were not obturating until I reached over 60 gr. At 65 gr, I got clean cases after firing and almost no unburned powder in the barrel, so I stopped there. It is also almost a case capacity load. I use mag primers and alox/beeswax.

405
11-28-2010, 02:38 PM
gear,

Sounds like you've done all the homework and looked at all the details. Only problem- leading and accuracy.

Unless something is wacky, these guns are capable of less than MOA accuracy with cast bullets. Velocity sells while accuracy is viewed as an academic concept.

The originals were developed around large, soft alloy, plain base bullets over BP at BP velocities .... and pressures. Try thinking 1150-1350 fps. BP loads with a solid column of powder with a hard card wad or two stacked and compressed under a plain-based bullet. That along with the vastly different gas/burn/pressure characteristics between BP and smokeless calls for a different approach. A long time ago I did the same things and made the same mistakes based on modern load data and modern thinking. Only problem- it did not work. Once I changed the concept in my mind from modern smokeless to old BP ballistics, my guns showed what they could do with cast bullet smokeless loads- MOA or better accuracy and no leading. The right bullet (.000- .001 over groove dia and GCed) with the right powder with the right loading technique along with a chronograph has allowed me to better approach the true potential of these big single shots. I have demonstrated that with two original 45-70 Trapdoors, an original 43 Spanish 1879 Rolling Block, an original 44-90 SBN 1874 Sharps and two modern Montana Sharps- 45-70 & 45-110. And, with BP my loads are paper patched, swaged, smooth bullets.... much more tedious and very different from the smokeless GC bullet game.

Unless you change your goal (accurate, easy to live with, efficient, reasonable recoil, etc.) type smokeless loads, there may be no need to go even to the 500 gr bullet. I know the 400gr varieties do extremely well out to at least 300 yds. I've found the 400-460 weight range to be an excellent compromise for most practical ranges and of course produce less recoil.

geargnasher
11-28-2010, 08:43 PM
gear,
[snip]
Unless you change your goal (accurate, easy to live with, efficient, reasonable recoil, etc.) type smokeless loads, there may be no need to go even to the 500 gr bullet. I know the 400gr varieties do extremely well out to at least 300 yds. I've found the 400-460 weight range to be an excellent compromise for most practical ranges and of course produce less recoil.

That is exactly my goal, not blistering velocity. I read Mike Venturino's book and took note of what he said about black powder, but this is my FIL's gun and I do the reloading in the family so we want to be able to store loaded ammo for a few years without worry. Also the convenience and cleanliness of smokeless powder are obvious benefits if he goes three states away to shoot for fun and doesn't have to soak the brass. Neither of us can see much beyond 400 yards with irons, so 1000-yard accuracy is moot.

You really said a mouthful when you mentioned thinking outside the box with this type of gun and cartridge, I already dropped back and punted with what I've found to be the usual line of thinking here. Think about it: I'm trying to push an ounce+ of fairly soft, plain-based lead down a .45 caliber barrel that has a 1:18 twist and is 30 inches long. Very heavy boolit, very long barrel, very slow twist. To me, that would require a very slow-burning powder for the best pressure/time curve, yet the system needs to operate at a very low pressure.

I pored over every book I have plus a ton of internet data on the 45/70 Gov't and the 45/90 with 400+ grain boolits and discovered some interesting things. FFg pressures ranged from 8,000 to 16,500 CUP between 45/70 400-grain starting loads and 45/90 535-grain max compression loads. That tells me that the best accuracy (apparently found at BP pressure levels with regard to PB boolits) will be with Trapdoor-level loads. Something else that jumped out at me was how Reloder 7 was consistently 200 fps faster with less pressure with every comparable smokeless load I found. It's possible to get 1700 fps with a 400-grain boolit at only 16,000 CUP using Reloader 7! I think that's worth a try. I'm also going to study some more and see why I can't use 748 or even 760/H414 without duplexing, I'd like to get at least 1500 fps with 400 grain boolits and less than 16,000 CUP so I can shoot comfortably, seal the brass, and have a reasonable trajectory out to 400 or even 500 yards.

And I haven't forgotten the advice about gas checked boolits or annealing the case necks, either.

Gear

405
11-29-2010, 01:46 AM
gear,

I think we're on the same page. My goals when starting to develop BP type loads using smokeless were pretty much the same as you described. Now I can shoot a decent string of 5-20 rounds or so, not worry about brass cleaning or immediate gun cleaning. After each shooting day I do completely clean the bore tho. But, it is one of the easiest cleanings of bores I do. Jacketed cleaning/ copper fouling is much more tedious and BP cleaning while not hard or tedious does require immediate attention. After shooting the smokeless cast rounds out of these rifles I vigorously run a jagged patch soaked with regular Hoppes 9 thru the bore, wait a couple of minutes and run another soaked patch thru. Then one or two dry patches to get it all out. Then an oiled patch. That's it. Takes about 10 minutes if I take my time, less if in a hurry.

I also see you've been studying the load data. Yes, Rel 7 is a good candidate. It shares some of the same qualities as 5744 but is slightly less bulky (more dense), is of smaller grain size and is very marginally slower burning than 5744. I use it in cartridges that have less expansion ratio than the 45 straight walls. It is one of my powders for the 38-55. I know some swear by the really slow powders for these low pressure, low vel loads but the theory of the SEE or detonation has always bugged me so I avoid small charges of slow powders in large cases.

You've probably noticed there is a lack of suitable regular production GC bullets offered for the purposes we're discussing. At the same time there is no shortage of plain base bullets available. That's why I went the custom mold route. Mountain Molds offers the online bullet design program. Within the limitations of the lathe bore machine capabilities, a very wide latitude of design is possible. What you design is what you get so extreme care and study should be taken when designing a bullet. There are other mold companies out there that do similar work. You might even send our own "Bullshop" a PM and see what possible bullets he can cast. Dan (Bullshop) and the family are good folks- none better. Before investing in a custom mold, wouldn't hurt to try some similar ones.

With the right bullet you might get to 1500 fps but I've been perfectly happy with a max of about 1350 fps out of my 45-110. With the heavier bullets, and even tho the gun is very heavy, recoil still takes its toll after a string of shots.

geargnasher
12-06-2010, 12:18 AM
OK, update time.

I worked over my 500 grain Lyman until the blocks lined up correctly and it cast round boolits, then lapped the bands another half-thousandth so it's throwing .459-ish boolits out of straight wheel weights. I cast these four days ago, but I couldn't wait any longer to shoot them.

In the meantime I purchased a pound of Reloder 7, and it sure is dense. I loaded ten rounds using the same methods above, one grain of fluffed Dacron between powder and boolit, lubed all the grooves this time. I struck a balance between the data for maximum level Trapdoor loads with this boolit and starting loads for the .45/90 with the same boolit, settling closer to the .45/70 max load due to the filler. Based on the difference in cases, primers, recoil, and point of impact, I found that a little Dacron in this case makes a HUGE difference in pressure, so I err on the side of caution.

I settled on 35 grains of RX7 with a Winchester standard primer. The difference was amazing. Recoil is stout, the barrel is absolutely lead free after the first ten, the point of impact at 50 yards is 1" higher than anything else I've shot with the same sight adjustment, and the group was a ragged hole for all ten rounds. A tight, dry patch through the barrel came out with just a little jet-black carbon on it, and there was the slightest trace of a lube star. I'm a long way from proving this one out, but this is the first postive result my efforts with this gun have yielded, so I'm very encouraged. Still might try a slower powder, but I need to talk with some of the SEE specialists first.

Gear

splattersmith
12-08-2010, 12:47 AM
Seems a lot use 3031 or 4198. I have tried both and like 4198 wir a square of dacron batting as a filler. More accurate than 3031 in my two 45/70s.

As to accuracy, try many things. Bullet and groove size matters. Bullet shape. Annealing helps with Starline cases and the factory actually recommends it. Differences in amount of powder, shooter hold, barrel harmonics, etc. All the normal accuracy stuff.

Usually it takes a while to sort out the 45/70 or 90 and cast bullits, so don't get obssesed with just one thing. It is always repeated -- each rifle has its own preferences, you just have to find them.