It's all in the details... or groove-dia. patched in 45-70

[martinibelgian]

The title could just as easily have been on the importance to keep good notes, actually - anyway, just a story on my latest episode with groove-diameter PP bullets and the 45-70.

End of last year, I was prepping my 45-70 (Greener-Martini with Metford segmental rifling) after its rethroating job for competition with groove-dia. PP bullets. These bullets are cast from a Nuemann mould , and spec'd to be an exact replica of the original Metford match bullet, weighing in at about 540grs with a 1:16 alloy. Naked bullet dia. is .451, and they are patched up to .458.

Load details as follows:
W-W brass, fireformed to the (generous) chamber, trimmed to 2.1".
CCI BR2 primers
2 drops at the 7.3 setting of my Uniflow measure (76grs), droptubed.
overpowder wad: Walters vegetable fibre .060
Bullet as above, unlubed, seated firmly into the lands.
Wiping routine is 1 wet, followed by 1 dry patch between shots

End of last year, I was getting pretty good results with this combination. However, when checking 1 last time before competion started for some chrono work, the groups became patterns, and MV's were pretty erratic. Not only that, but also I had 2 case separations... (those trapdoor stuck case removers do work very well indeed :( )

So I tried lubing the patches in order to eliminate that issue, and yes, it worked - but accuracy still remained so-so. Net result? I used another rifle for competition, and left the cranky 45-70 in the gun cabinet untill recently, when I finally took the time to do some searching.

Turns out I 'misremembered' the correct powder charge when I made up some cartridges last time, stuffing in 2 x 7.6 instead of 2 x 7.3 - about 2,5 grains more, and - more importantly - quite a bit more compression.
After realizing the error, I made up again some rounds, this time according to the original recipe, and tested them. Groups were quite a bit better, but not up to the original results. There also seemed to be a tendency towards vertical stringing on the target, I couldn't accurately 'call' my shots . Some more investigating to do... Still, no more ruptured cases, so progress was being made.
This time I turned my attention to the rifle, and found that the forearm screw was just a little bit loose. It was just a few seconds work to get out the screwdriver and tighten the screw.
Yesterday evening I did some more testing, and voilà! Accuracy had returned to the usual, clammish groups of last year, so I was ahappy shooter!

Moral of the story? If you keep complete and detailed notes, that will avoid lots of lost time and frustration. Lesson learned the hard way.

Other point? With such a hard alloy for a PP bullet in 45-70, there seems to be only a very narrow 'accuracy band' available, before accuracy starts to degrade and other issues start to manifest themselves...
OTOH, in the sweet spot, accuracy is excellent, giving those gratifying ragged holes if I do my thing (shooting prone, 2-point sling only, no rest)

[Doc Highwall]

A combination of too much compression and a rough dirty case interior give the compressed powder plug something to grab onto will rip the cases in two.

[martinibelgian]

Yes but - don't forget this is a groove-diameter PP bullet, unlubed - it will also grab the case walls quite a bit more as quite a bit is seqted into the case. I believe the combination of the patch, more bullet upset and the seriously compressed powder plug all contribute to the case separations.

[Lead pot]

I get case separation when I shoot PP close to groove and right at bore diameter if I dont use a lube wad in the .40-70 stretched 30/40 brass and in the .44-90 BN, but only when I use swiss powder, and more so with 100% cotton rag then 20% cotton.
I don't have this problem using other powder. I discount dirty brass it is clean.
I dont shoot unlubed anymore.

[RMulhern]

See my post 600 yd. KIK 1F! That powder was compressed (actual) .735"! I always lube the interior of all my cases using powdered graphite; makes a big difference on stroke pressure required and like Leadpot....I discount dirty cases as I run them all through a tumbler using ceramic media! I use a shoe dauber to apply the graphite into the cases. The group shown was not the best I've fired previously from 600 yds. but using a totally new powder (KIK 1F) it gives me hope that eventually I'll refine the present 'duck feather' such that there will be improvement! When compressing to the above depth...I DO NOT compress with a wad in place! If I do...case bulge will result! I only compress with the powder in place and THEN I insert the OPW with a dowel!

[montana_charlie]

Since going to PP I have always patched to groove, always seat unlubed bullets deeply, and have never had a case separation.
As for graphite inside the case, I expect there is enough on the powder granules to account for that.

CM

[RMulhern]

Since going to PP I have always patched to groove, always seat unlubed bullets deeply, and have never had a case separation.
As for graphite inside the case, I expect there is enough on the powder granules to account for that.

CM

montana_charlie

As I previously stated....lubing the interior of the case w/powdered graphite makes compression of the powder much easier!

[Doc Highwall]

RMulhern, I think you are on the right track by cleaning the cases and lubing the insides of the cases with powdered graphite. Have you tried anything besides the powdered graphite?

[RMulhern]

RMulhern, I think you are on the right track by cleaning the cases and lubing the insides of the cases with powdered graphite. Have you tried anything besides the powdered graphite?

Doc Highwall

No sir I haven't; works quite well for me!:bigsmyl2::arrow::[smilie=s:

[martinibelgian]

After reading the above, I believe I'll try lubing the inside of the case necks with a smidgen of bullet lube. After all, it's the case wall being gripped, so that should work. Lubing the patch is another option, but not so good IMO. We'll see...

[catboat]

A couple of thoughts:

What if you sized your naked bullet a bit larger, to .452", and wrapped to .459 or .460" diameter? You may get better accuracy-depending on bore/groove diameters, and throat size (better gas sealing for more consistant pressure and hopefully accuracy).

What if you combined the larger naked bullet sizing (.452") with a softer alloy? 1-20? 1-25, 1-30? Softer PP wrapped bullets will generally produce lower pressures (and velocities) at comparable powder charges (loading conditions) than of a harder bullet. This may provide more consistant MV/pressures and hopefully accuracy.

Have you tried Winchester or magnum primers? They tend to burn hotter, and may give better combustion. Easy enough to test.

Do you uniform your primer flash hole? I use a K&M flash hole uniformer. It has the stop depth coller at the drill end of the unit. Some devices have the depth stop collar that uses the case mouth as the reference point. These aren't so good, as your case length has to be the same-so it adds variability to the procedure. Uniforming primer flash holes, in my opinion, is one of the most important steps to eliminating pressure/MV variations and translating to improved accuracy.

Good luck.

[martinibelgian]

No, can't size the bullets larger - they're as cast. I can only increase the paper thickness, but prefer to have the paper at groove depth.
Softer alloys will work, but need a lower charge. I tried 20:1, and that alloy needs about 70grs of 1 1/2Fg. Too much powder behind too soft a bullet will give you too much bullet setup (nose slump), especially with a bullet like this, which has a long elliptical nose. The harder alloy, however, is for more powder and LR work.
Setup seems to be quite good - at least, when my patch was a bit shorter, I found traces of leading in the barrel, probably indicating setup beyond the edge of the patch. So I used a slightly longer patch.
As to primers, my experience tells me the softer primers work best with BP - the stuff is easy to light. I don't want the primer to 'bump' the bullet forward before the powder ignites. I shoot fireformed cases, no neck tension.
And no, I don't uniform primer flash holes. Maybe I should give it a try - but the load is giving me ES of below 10 fps, so things seem to be quite good already.

[martinibelgian]

Well,
my temerity was punished - I took the loads with the lubed case necks to a match, and proceeded to shoot a retty lousy score - patterns, not groups... :( Apparently, the addition of a smidgen of lube was enough to seriously degrade accuracy. And of course I had to take it along to shoot a match. it was even so bad that my score with military BP rifle was better - and that score wa not really that good...

[Doc Highwall]

That is why I asked RMulhern if he tried any thing else besides the powdered graphite. This came up because of case separation with heavily compressed charges of black powder. That is when I said that having a rough/dirty case interior gives the compressed powder something to grab a hold of and rip the case in two. RMulhern said he dusted the inside of the case with graphite and he is shooting PP bullets. I asked him if he tried anything else and he said no.
I said he was on the right track but I should have mentioned with a dry lube like the graphite, mica, or talcum powder. A wet lube like for grease groove bullets will add a stickiness of it's own that I would not try.
I would use some thing like ceramic or stainless steel tumbling media to get the cases clean and smooth on the inside. The dry lube is for heavy compression of the powder.

[martinibelgian]

My cases are pretty clean too - I use an ultrasonic cleaner. Still I do find some stretched cases after firing (between .001 and .005). However, if I have to choose between stretched cases and patterns for groups, the choice is easy... I'll try some graphite maybe, maybe also change the veggie wad for a card one, we'll see...

[montana_charlie]

I still feel that the graphite already on the powder granules is sufficient to satisfy any need for a 'lube' during powder compression, but I (too) just tried some 'lubed PP ammo' with crappy results.

I decided to try felt wads saturated with bullet lube to see how that affected fouling with PP loads, and reasoned that insertion of the wad would also 'lube' the inside of the case neck.

The day was cool (55 degrees), cloudy (threatening rain), and the humidity was 38%. The barrel never got more than 'slightly warm' to the touch.

The fouling was crusty, dry, and had a consistency like 'potting soil' as it layed on the first wet patch used when wiping between shots. I suppose some of that material was the lube, itself, from the felt wad.
I was disappointed that the following veggie wad did not scrape a good amount of that 'loose stuff' out during it's trip to the muzzle.

No, none of the cases stretched or separated with the lube in their necks, but they never do, anyway.
The real proof of the pudding was the target, itself, which was so bad ... (How bad WAS it?)
It was so bad, I was inclined to pick it up with a Pooper-Scooper.

So much for lubed felt wads ... now I wonder if it's worthwhile to screw with lube cookies.

CM

[martinibelgian]

Of course, I know the solution - got back to 20:1 alloy and the lighter load (70grs). But I still have quite a few of those 16:1 alloy bullets, the experiment will continue.

[Kenny Wasserburger]

I know of a fellow that tried powdered Graphite on the patched bullet with pretty good Results at Phoenix Regional and America's Cup Matches last March, -350 Mesh Graphite was imployed in the test.

Chronograph Testing was conducted at the Ben Avery Silhouette range with Graphited patches vrs unGraphited patched bullets, exact same load. The Graphite Patched rounds avg 6 FPS slower and had almost half the Extreme spread and a lower SD then the Ungraphited Load. This test was conducted before the matches after the first day Practice session, using a Oheler 35P chronograph set up 28 feet from the Muzzle. Too avoid Issues with wads.

As I recall he brought home a Cup from the America's Cup Match too boot, and he has been trying for one of them for several years.

The Lunger
KW

[Lead pot]

KW.

How many shooters were in his class to win that cup?
If the Graphite patched bullets were used with 50-60 shooters not using it might be worth looking into.
I tried graphite several years ago and I developed a problem with that stuff coting the bore like molly does.

[Kenny Wasserburger]

Kurt,

As I recall there were 4 or 5 shooters in that class the heavy gun for the Cup we had a total of 5 also in the Regional. One of them Was Darrel Tonn 4-5 time Nationals Scope Mid-range and several times Long Range Champion. No slouches for sure. And the Cup is shot with No Spotters, which I like a great deal.

All I shared was that the chronograph results showed some very consistant muzzle velocitys with the Graphite.

Your test of several years back? where you wipping between shots?

I agree that a build up, like Moly could occur with out a doubt and be an issue, The vote is still out on using it on patches in my limited testing.

The Shooter did finish in the top half of the Cup, 38 shooters for it, a few more for the regional.

I know one shooter was PP and using the small bullet thick paper at Phoenix, his scores were in the Tank.

I understand you did well at Lodi, glad to see you were there and did well, will we see you at Raton?

KW
The Lunger

[Kenny Wasserburger]

Martini,

Wet Chamber????

Are you wipping between shots?

A wet Chamber will surely do that to ones cases.

The Lunger

[Kenny Wasserburger]

As I mentioned the only real benifit, of the Graphite, I could see or measure, was the Chrono Data, However no case issues, however my bullets are slip fit to the case and are patched to bore.

The Rifle 2 weekends past shot very well off X sticks prone, with out the Graphite and the change from Poly wads to Rubber Cellulose Wad in place of the Poly. Shot a 23/48 at Alliance Last Saturday, with Match won by a 35/48 from Mike A. Jim Terry was second with a 34/48 and using a 45-100 ballard, with GG bullets and white Lighting lube. He just called me to tell that he had tried the rod pounded down the barrel of both the 100 and the 38-50 his daughter was using, and neither had any lead at all with the White Lighting Lube.

KW
The Lunger

[Lead pot]

Kenny,

The amount of shooters was a poor reference but once I hit the post button and rethinking what my example was it was to late.

What I should have said is, if th shooter normally shoots an agg in the say mid 400 Rd's and now shooting in the lower five hundreds that is an improvement I would be chasing myself.

I was wiping between shots Kenny. At this local I get enough moisture using the tube.
What I was seeing when I used graphite was in time my patches never came out white they always looked gray and would find flakes starting to show up and the last thing I wanted was having fouling trapped under that stuff and starting a rough bore with pits so I quite using it. I never found any improvement in the accuracy that I normally got with out it.
Yes I shot the best I could at Lodi but I dropped 6 or 7 completely off the paper in the two days, but mostly on the 900 when it clouded over and my floater gave me a problem seeing the 900 th first day and the 1000 on both days. You just cant hit right when all you see is a fuzz through the aperture.
I shot one 800 with a 90-2X for the best relay and ended with an agg of 457-5X but the dirt diggers off the right and left side hurt, but regardless I feel pretty good shooting that using a new load of 1.5 KIK in a rifle never used in competition at a last minute change and only shooting ten rounds in my back yard to see if they print tight.

[Kenny Wasserburger]

Kurt,

Phoenix is a tough game the Cup tougher yet, as no spotters. So I am thinking my 444 Score which was in the top half of all the shooters was pretty good for the Graphite test. No huge gains seen in score with it as my personal best in Creedmoor at Raton or Phoenix is in the 470's Range. I think Missoula maybe my highest score ever. And that made the Top Ten at Raton that year, I have seen national championships (dependent on Conditions) in the 490's to 508 lows. Usually they are often in the 515 to 530 range when milder conditions.

Lodi has always been a high scoring place, kinda like Missoula.

Though with PP one of my highest scores ever at Raton did not even place in Scope in 2009, Darrel Ton edged me by 13 points.

KW

PS Kurt there is a Edit button to change Posts??????
the Lunger

However: I agree that it may rear its ugly head with issues of build up in the bore as you mentioned. Alliance was shot with out, and the only test session I got with the Rubber Cellulose wads showed excellent accuracy at 200 so I went with an untested load also to Alliance for the big gun.

Glad to hear you did so well with the KIK, it is my next test subject also.

KW
The Lunger

[Lead pot]

KW

PS Kurt there is a Edit button to change Posts??????
the Lunger



KW
The Lunger

[smilie=f: ya I know, I'm not one to back track :smile:

[martinibelgian]

Kenny,

1 wet (moist actually), 1 dry between shots - with special attention to the chamber. Then again, shooting groove-dia., I have quite a bit of bullet in the case, so that might also be a contributing factor. A PP bullet would grab the case walls quite a bit harder than a GG bullet - or a bore sized PP bullet seated way out into the rifling.
FWIW, I once tried (dip-)lubing the patches, and that also solved the issue - but accuracy was not really up to my standards (to put it kindly).

[Don McDowell]

Martini, have you tried just lubing the patch with jojoba oil after the bullet is seated in the case? I tried that after reading about it in the 1875 Remington catalog (only they said to use spremicetii and we all know killing sperm whales is verboten now:mrgreen:) Anyway it wasn't a real scientific experiment, but I did go 11 rounds without wiping or blowtubing and had no leading when I wiped the barrel out. Cant say a whole lot about the accuracy as I was winging those at the 1000 yd gong offhand using the laddder sights... Got it once, and poked the 800 yd buffalo once as well.

[martinibelgian]

No, I haven't tried Jojoba oil on the patch yet - but I'm afraid that wwhen doing it afte rthe bullet is in the case, lubing just the exposed portion won't really help anything - it's the part in the case the probably is causing trouble.

[martinibelgian]

Update:
I took the rifle load combination out for a new test yesterday - this time unlubed case necks, dry patches. The main intention was to determine the cause of inaccuracy at my last outing.
I fired a complete match (i.e. 13 shots) at the local 75m range the usual way - prone, with sling, unsupported.
Wiping routine was unchanges - a solution of 10:1 water and cutting oil for the moist patch, followed by a dry patch.
The 1st shot (from an uncleaned, oiled barrel) was waaay out - about 7 minutes high, but pretty much centered. The next 12 shots were without sight adjustment, and landed where they were supposed to land: clustered mostly in the 10-ring, with however 2 shots that wouldn't score as such (we need 50% in the higher ring to get the higher score - MLAIC rules).
There maybe was a bit of vertical in the group, but obviously only minor. I resume that I now have to believe that such a small change (a smidgen of lube inside the case necks) can indeed have accuracy consequences.of that magnitude... I'll try to put up the target this evening.

[Lead pot]

My .44 BN will pull the case necks off if I dont use a lube wad especially when using swiss powder for some reason.
With the straight wall cases I don't have this going on.
I suspect the bottle neck is doing this when the powder goes off in the large powder chamber then reduced to a smaller diameter in the neck raising the pressure.
The velocity is a lot faster using the same powder load and bullet weight in a straight wall case is slower then the bottle necked case.

[martinibelgian]

I once tried a few (very few) tapered PP bullets in my #2 Musket - also a moderate BN. Those apparently didn't give me any issues, but then I used only about 90grs of Swiss Fg - and the fact that the bullet was tapered might also have something to do with it.
Results of the few shots tried were promising though - but that's another project for sometime in the future. And the sample was probably too small anyway to draw conclusions from. Given the price of #2 Musket brass and the conversion work required, I for sure wouldn't appreciate a ruptured case....