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I have used 4' long pvc pipe in 8" diameter to make a sealed tube on one end. Use a mix of ATF (automatic transmission fluid) and kerosen to soak mag tubes and barrels or actions. Works well for soaking the long stuff. The parts washers at the shop are OK, but the tub is only 24" x 36" I hope you get to shoot it Saturday. Looking forward to more photos and targets.
 

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Steve, I re-read this and just want to clear up a question. Are you using a 38-40 lead bullet at .401" to slug your 38-40 barrel? If so your measurments will not be very accurate. When I slug, (and everyone will have there own opinions) I like the lead slug to be longer in lenght. about 3/4" long. I like the diameter to be .005" to .010" larger in diameter to what I am expecting the groove diameter to be. I use gun wax on the bullet and bore to help with lubing the barrel for pushing the lead through. Micrometer with ball or points work well for measuring, but a good steel caliper will also work. You may have a candidate for a PSB load, depending on you measurment numbers. Or some hollow base lead bullets. Again these are just my .02 cents worth, lots of ways to come up with the best load for your rifle.

Thanks for posting the photos, target and progress.
 

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Steve what diameter did that bullet measure prior to slugging the bore? The smaller diameter measured on the lead is the bore diameter. I'm thinking the groove diameter did not fill out on your slug. When i slug there will be a nice lead ring that falls off the slug as it is entering the barrel. You will see the lead is smeared and pushed back.

Ammunition Bullet Metal Brass Gun accessory


In these photo the ring is in the front left corner of the frame. That fell off the slug as it was being pushed into the barrel that was being slugged.

Metal


Finished slug will reveal the bore and groove diameters.

A 45ACP case with get you a .450" slug. A 44-40 case with get you a .432 slug. A cut down 30-30 will get you a .400" slug. and they are long enough for a nice bearing surface and easier to measure into the cuts on the lead made by the lands.
 

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I'm thinking your bore measurement is accurate and spot on at .395" And the pulled 38-40 bullet would work well for getting that measurement. I'm just thinking that bullet might be .401" right from the start. Your 50 cal. bullet would work good, but those are usually .458" IIRC. But measure yours to be sure. Round balls are harder to measure and can become out of round during the slugging process. I tried round balls early on and they did work, just harder to measure accurately.
 

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What you are saying would make sense that it started to lead due to poor bullet fit. Started key-holeing. I think matching bullet to your groove would be a great first step. Your going up in diameter is in the right direction. What diameter are other b38-40 users using in vintage Marlins?
 

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Steve, go with PSB and A2400 it will save you a lot of time and trouble. I'm no expert, but you are not going to be able to fill that groove diameter with just using larger bullets. You'll run into chambering issues. With rifling that is that deep, I have had success with two different approaches at this issue in my 1894 44-40. One is the above mentioned PSB, the other was Swiss black powder, SPL lube and 5-7 BHN lead bullets. Both work well for me. And the more information I gather and read the more I think the deep rifling is fairly common on the pre smokeless era rifles. Just another reason why hand-loading is a big benefit for matching the components that work best with each particular firearm. At one time I thought I'd be able to load two 44-40 round, one rifle and one pistol. Boy was I wrong. In hind sight if someone wanted simple and just one loading I'd go with 32-20 a Colt SAA and a Marlin 1894CL. both can handle the 10gr of A2400 and both like the 115gr. bullets. But simple is not as fun or educational. Happy loading!

Have a great Holiday weekend,
 

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I have found bore dimensions that were what I was expecting, but the groove diameters are what caused all the chaos. The .010" deep grooves are a challenge to bump up and fill. The .003" to .004" grooves are a lot easier to fit bullets to. Rifles I have from 1895 to 1911 all in 44-40 and all four have different groove diameters.
 

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Finally slugged my barrels. The 1889 made 1890, has a bore size of .397 and a Groove size of .403-.404. No PSB needed here.

------------------------- The 1894 made 1894, has a bore size of .395 and a Groove size of .410-.411. Will need PSB here.

Would be curious as to how tight a 1888 barrel would be.

Question will it hurt to just use the same PSB load in both?
Hey Tom, PSB can be used in both and will not be detrimental, but why if you do not have to. PSB will increase velocities and pressure. I drop 1gr. of A2400 in the 44-40 and still maintained the same velocity. So same bullet, same brass, same primer, but 1gr less or A2400 an .7cc of PSB added, and I was still at 1300fps. Tried this with several charge weights in the 44-40 using A2400 and the pattern was the same. I can look at my data, but IIRC if I just added the PBS to a known load with out a decrease in powder, I would increase velocity in the 150 - 200fps range. I see no harm in using PSB in rifles when it is needed. Care should always be top on the priority list. Very little published data on PSB and pressures. But PBS is very light weight and works great for this application.
 

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Just a comment and my thoughts on the DCB 20:1 8-9 BHN bullets. LOU's (Lever Addict) recipe is a perfect balance of velocity, fps (feet per second) and BHN (brinell hardness number) and the use of PSB (polyethylene shot buffer) And I think for the 38-40 his load would be tough to improve on. Now if one where to try to increase the velocity of this load and attempt the 1500fps area I think you will have issues with the bullet. When I used the 20:1 DCB in the 44-40 as I went up in velocity it started skidding or stripping down the barrel and did not engage with the rifling very well. The bullet was too soft for those velocities and pressures. Experiment and record your data and findings.
 

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I'll bet other manufactures and other types of PSB have different weight to volume ratios, but the BPI blue label white powder stuff is what Midway sells and what I have been using. I know Lou uses the same product and I think 45BearGun does also.
 

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I use .7cc in the 44-40 and have loaded some with 1.0cc. Be careful with the PSB, you are taking up case volume with it, increasing pressure and velocity. Using any filler is reducing the amount of space inside the case and in affect with a smaller case volume and using the same powder charge, pressure will increase. Polyethylene Shot Buffer is worth using on rifles with deep (.010") rifling and will improve the gas cutting on the lead bullets. PSB is safe if you pay attention to what your loading.
 
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