Slugging a Barrel

DiMP

DiMP

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I have now managed to collect a good quantity of 303 British brass to reload. Because they (two #4, one SMLE) are guns I am hoping to begin shooting more, I have been looking into reloading with cast bullets (from Jet, not into casting myself yet). After much reading, it is advised for older guns to slug the barrel so I can determine proper bore size since the cast bullets come in a couple different sizes. I plan to slug each one, and, ideally I won't have 3 entirely different sizes. Now here are my questions on slugging.

I don't have a bench vise; my concern is smacking something down the barrel and putting the force of each whack onto the contact points between action and stock. How much force is it going to take to push the lead ball down the barrel, and is that enough to possibly damage the wood (or other bits)?

Second, being in a small town, I was hoping to use what I already have. The tutorials I was watching, they used a 30cal lead round ball. I shoot a little black powder, and my BP revolver is a 36 cal (0.375 round ball). Am I going to be able to use that? I assume it should just take some extra love to get it started

Lastly, and less "slugging" related and more once I start reloading cast bullets. I can't seem to find an expander die, is there a temporary *something* I could use until I come across a die to flare the case necks so I don't shave the cast bullets on insertion?
 
I am probably (no, not "probably" - change that to "definitely") no expert, but I had bought a box of Hornady .375 diameter round balls exactly to do what you propose. I set up the rifle vertically, but I do have a bench vise - have made "soft jaws" from leather from an old belt - clamp the barrel vertical. Then set a round ball on the muzzle. A couple taps with steel hammer to get it started - then switch to short length of wood dowel so I don't bugger up the muzzle - keep tapping until the slug is within the bore - the excess mostly shears off. Then, various lengths of steel rod to get it going down bore further - often get to point that I can just push it with a rod. Kind of pretend that I am "feeling" whether it gets tighter or looser as it goes. Most I have done are simply to tap in maybe two inches, then drive out from other end - really just slugging the muzzle diameter. For chamber end, I know there is a procedure called "lead packing" to get a ball seat diameter, but I have never done that - I do a cerrosafe casting at that end, to get that dimension.

Depending what 303 rifle you have, you will go pretty much nuts trying to get an accurate diameter measure for the 5 groove barrels - the riflings /grooves do not line up across the diameter, so need to use a V-tool, cut to appropriate angle, a micrometer, and a calculator for the math and trigonometry involved.
 
The gun should be able to handle the forces of slugging the bore without any issues. It's more gentle than recoil but might be in the opposite direction. If you can get a second person to help hold the rifle it's easier to keep things lined up.

The .375" balls are quite a bit too big but you can narrow them down a little closer to the size of the neck by rolling between hard plates or by gentle tapping around the circumference.
Another useful thing to look at is how big the fired case is at the neck. If the chamber or throat is on the large size it might be worth trying bullets as large as possible that still chamber easily.

The necks can be belled a little using something tapered with a profile you like. A long punch, a neck chafer tool turned twisted backwards so it doesn't cut, needle nose pliers.... Look around and see what is worth a try.
 
Another "issue" with previously fired 303 brass - it headspace on the rim, not on the case front shoulder. Many 303's have overlarge chambers - cut that way on purpose by military - was meant to handle a cartridge - that fired once, and was discarded. Can often result in case stretching that exceeds the brass capacity - results in a case head separation ready to happen - inside the case, near the solid head, might be a groove all the way around - the brass is much thinner at that point - was caused by firing in a overly long chamber. It worked as designed - cartridge fired, did not burst and was extracted. But re-loading that case was not part of the original design.

So either really good light to visually inspect, or make a right angled "feeler" - sharpened paper clip or similar wire - with perhaps 1/8" to 3/16" right angle at end - can side down into the case and feel for that groove along the case wall - right down close to the solid case head. If groove is there, inside, can expect that case to separate on the next firing. Rim of case will come out on bolt, but the case body will still be inside the chamber. Well worth your while to get a broken case extractor if you are going to fire reloaded 303 British shells. I think Marstar still lists them for sale. Some guys successfully get a separated case body out of chamber by ramming in another loaded cartridge - usually sticks tight enough to the broken off case body that both come out together.

If you do get a case separation, do not be tempted to "dig it out" with something makeshift. Has been more than one post on the resulting gouges left in the chamber by attempting to do that. A proper extractor will get it out without damaging the chamber at all. Like Boy Scouts motto, I guess - Be Prepared!!!
 
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vagrantviking said:
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The .375" balls are quite a bit too big but you can narrow them down a little closer to the size of the neck by rolling between hard plates or by gentle tapping around the circumference.

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Click to expand...

Absolutely correct!! My first attempts at this - had 1/2" thick block of steel - drilled in about 3/8" deep with slightly oversize drill bit. Had some sheet lead - probably pure lead - very soft. Melted it and poured into my "mould" - managed to get it out. Drill bit front end resulted in mild taper to that lead "slug". Was able to tap in and get measurements. I play with various older milsurps that vary from under .264" (if "good") to over .323" (if worn) so I thought the .375" Hornady round balls would be less fussing. Probably would buy some .358" or so if I found them. Pretty much needs to be very soft lead - even wheel weights made slugging harder to do than with pure lead. Sawed-off or squared-off muzzles seem to shear excess lead from the slug "easily" - has been mostly what I was doing - to slug it to see if I have gotten back to correct bore diameter or not...
 
Starting a lead ball with a hammer at the muzzle works. Oil the barrel, first. Your ball sounds kinda big...

Just for your amusement, here is how I do it.

I take an unsized lead bullet and seat it over a very mild charge of pistol powder. I thin shoot it at a big ball of pillow stuffing. The bullet wraps up the stuffing and flies about 20 feet, dragging the stuffing. I then unwrap a pristine engraved bullet.

I have also done the same thing by just shooting into the swimming pool (when She Who must be Obeyed) is not home.
 
DiMP said:
Lastly, and less "slugging" related and more once I start reloading cast bullets. I can't seem to find an expander die, is there a temporary *something* I could use until I come across a die to flare the case necks so I don't shave the cast bullets on insertion?
Click to expand...

Lyman makes type "M" expanders that aids in straight inline bullet seating. Look at the shape and design of the expander.

Lyman M-Die Expanding Plug Part Numbers
http://ps-2.kev009.com/ohland/Cast_Bullet/Lyman_M-Dies/Lyman_M-Die_Plugs.html

https://www.lymanproducts.com/rifle-neck-expanding-m-dies

Improves accuracy of cast and jacketed bullet reloads. Doesn't stretch cases as does standard expander button. Extends case life. A "Must-Have" die for the cast bullet or flat-base bullet user.

The first step expands the inside of the case neck to just under bullet diameter for precise case neck tension in the finished reload.

The second step expands the case mouth to bullet diameter or slightly over. This allows the jacketed or cast bullet to be started perfectly centered in the case mouth and properly aligned with the axis of the case neck.

Note: By adjusting the neck expanding plug slightly deeper, the second step also provides a slight flaring of the case mouth for reloaders using cast bullets. Improve your bullet seating for your rifle today with Rifle Neck Expanding M Dies - shop Lyman!

Below a .223 Lyman type "M" expander for the 223.

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Below the Lyman type "M" expander keeps the bullet from tilting during seating.

vwgkeH3.jpg


Below rather than shooting cast bullets I shoot reduced loads with Hornady .312 pistol bullets. I use either SR4759 or Trail Boss, these loads make the brass butt plate "softer" when fire forming 100 or more cases.

HHDfGl9.jpg
 
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DiMP said:
I have now managed to collect a good quantity of 303 British brass to reload. Because they (two #4, one SMLE) are guns I am hoping to begin shooting more, I have been looking into reloading with cast bullets (from Jet, not into casting myself yet). After much reading, it is advised for older guns to slug the barrel so I can determine proper bore size since the cast bullets come in a couple different sizes. I plan to slug each one, and, ideally I won't have 3 entirely different sizes. Now here are my questions on slugging.

I don't have a bench vise; my concern is smacking something down the barrel and putting the force of each whack onto the contact points between action and stock. How much force is it going to take to push the lead ball down the barrel, and is that enough to possibly damage the wood (or other bits)?

Second, being in a small town, I was hoping to use what I already have. The tutorials I was watching, they used a 30cal lead round ball. I shoot a little black powder, and my BP revolver is a 36 cal (0.375 round ball). Am I going to be able to use that? I assume it should just take some extra love to get it started

Lastly, and less "slugging" related and more once I start reloading cast bullets. I can't seem to find an expander die, is there a temporary *something* I could use until I come across a die to flare the case necks so I don't shave the cast bullets on insertion?
Click to expand...

I load my cast bullets in 303 with a mouth flare. My temporary fix (for the last 30 years) has been to adjust a 8mm decapper die so the expander button kisses the 303 case mouth.
 
Thanks for the insight everyone. Thursday and Friday the weatherman says I'm to expect a rain/snow mix, so I think I will attempt it then. I also found a former-sponsor who carries the expander dies, so I think I'll order one of those since I don't have any other dies (like 8mm like Ganderite suggested) that would be bigger than what I am reloading
 
I've used a tapered punch to lightly expand a case mouth when I couldn't find anything else. Use a light touch.

Fishing stinkers are usually soft lead and work well for bore slugging. They're usually easy to find.
 
Like stated above, I was able to find (and now order) a Lee Universal Expander from a former-sponsor (it's only $23)
I was able to slug two of my rifles today (one SMLE, one Carcano). I used the .375 round ball that I had squished more oval before tamping in. I should be able to slug the other two No4's I have then I'll be placing an order from Mr Jet (or do I wait for the new 30-30 mold to be in....?)
 
Be careful with the Lee expander. If it's still the same design as the one I have it has a pretty steep taper and only bells the mouth. It doesn't really expand any amount down the neck.
Cases have to be trimmed the same or any longer than what was used to set the belling die tend to get mangled.

Sounds like you are well on the track to getting those old guns barking again. It's a fun journey.
 
vagrantviking said:
Be careful with the Lee expander. If it's still the same design as the one I have it has a pretty steep taper and only bells the mouth. It doesn't really expand any amount down the neck.
Cases have to be trimmed the same or any longer than what was used to set the belling die tend to get mangled.

Sounds like you are well on the track to getting those old guns barking again. It's a fun journey.
Click to expand...

Thanks for the heads up. This is the typical order I do things:
De-prime, wet-tumble, resize, trim (assuming resizing might stretch the case a minute amount?), de-burr, [Flaring will go here], prime, powder, seat bullet, crimp if required
 
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