Why slugging is hard, and a question

[LittleBill]

I thought someone here could relate to this one. Here is a picture of what I have to work with in slugging a .30-06. shoving the ball through the barrel was easy enough. Measuring it wasn't. This is the story of my life. Anyway, maybe someone here will get a laugh out of this. This is my paw holding my micrometer and the slug. As you can see, it reads right at .307.

http://i119.photobucket.com/albums/o159/FotoBill/handcaliper_zps4ebbcbfa.jpg (http://s119.photobucket.com/user/FotoBill/media/handcaliper_zps4ebbcbfa.jpg.html)

Now for the question...

The ball was .310, or close to. It met with resistance, and as far as I could see, filled the barrel completely at the muzzle. As I tapped it in the tapping thereof got easier and easier until I could just push the rod and the ball fell out. Should I try a bigger ball? I pushed two balls through two barrels and got a nice shiny band all the way around each, so I am assuming I got good contact all around the barrel for at least part of it. If I were to order a mold in .310, size to .309, I should be good, huh? What say the experienced ones here?

[WILCO]

I would've used a bigger ball. Haven't slugged alot of barrels, but would've expected more deformity from the ball being pushed through.

[wallenba]

It's soft lead. Find a flat surface and a flat faced hammer. Give it a few taps and measure. Try for about .350, that will give a wider area as well to measure. A vise can also flatten it . Careful positioning while tapping it in the bore will give good results. You will want to see a ring of lead left behind as the slug goes down the bore. That's the indication you've stuffed the entire bore. I'd bet you will get a different reading than before.

[fouronesix]

Have done it with all manner of "slugs". Usually best to use pure lead or very soft lead. If using a roundball, I usually start with a slightly larger ball, lube bore well, start with a slightly undersized brass punch then finish pushing through with a one piece steel rod. Another slug that works well is an oversized fishing bullet sinker or even an egg sinker. Another type I've used for 30 caliber bores is a pure lead cast 32 cal bullet pushed through a 30 cal bore.... and so on. If I think I'm not getting a good reading or if the results seem odd, I'll repeat the slugging 2-3 times to verify.

If you are confident your groove diameter is .307 then sizing to .308-.309 usually works well- especially if the bullet is gas checked. If plain base then other things come into play and the whole system must be "happy" or the whole exercise can get frustrating.

[LittleBill]

Try for about .350, that will give a wider area as well to measure.

Yeah, .360 is real close to .35, right? So I just smacked a .357 boolit into the muzzle. It did not get very far, but I did get a much larger surface to measure, and it was right at .308-, or a few 10,000ths from my first measurement.

I am going to look around and see if anyone close to me is shooting cast .30 and get a few boolits from them. I've got the slugging process down pretty good now. It is just getting the lead to a good size, and then actually handling it that I'm still working on.

[wallenba]

Yeah, .360 is real close to .35, right? So I just smacked a .357 boolit into the muzzle. It did not get very far, but I did get a much larger surface to measure, and it was right at .308-, or a few 10,000ths from my first measurement.

I am going to look around and see if anyone close to me is shooting cast .30 and get a few boolits from them. I've got the slugging process down pretty good now. It is just getting the lead to a good size, and then actually handling it that I'm still working on.

A thirty caliber cast will likely be a harder alloy, and you will have a bear of a time getting it through the barrel of a rifle. Also, hard alloys will rebound a bit (grow). Dead soft lead will not change. Stick with pure lead, it's the only way to do it accurately.

[Bent Ramrod]

You may be fortunate. Try tapping another ball into the chamber end and push it 1/4 way up the barrel and then back out the chamber end. Measure that slug and compare it to the one that ypu pushed from the muzzle end, From your description of the ball getting easier to push as it went from muzzle to breech, it sounds like your barrel might have a slight choke in it, which is a good thing for cast boolits.

Another slug tapped into the leade just ahead of the chamber should give you an idea of the correct diameter to size your boolits to. Or you could just start at .311, see how it shoots, and size smaller if it seems to help.

[LittleBill]

You may be fortunate. Try tapping another ball into the chamber end and push it 1/4 way up the barrel and then back out the chamber end. Measure that slug and compare it to the one that ypu pushed from the muzzle end, From your description of the ball getting easier to push as it went from muzzle to breech, it sounds like your barrel might have a slight choke in it, which is a good thing for cast boolits.

Another slug tapped into the leade just ahead of the chamber should give you an idea of the correct diameter to size your boolits to. Or you could just start at .311, see how it shoots, and size smaller if it seems to help.

You know, I was wondering about that. I had read some on the board here about that being a good thing, and I was trying to figure out if the slug was moving easier because the bore was increasing in size, or if it was just so well fitted by then it didn't matter. I guess more slugging is in order.

[DrCaveman]

Littlebill

If it ends up you have a tapered bore, could you let us know what rifle you are slugging? I understand that some makes & models have tapered bore, and your results might influence someone considering purchase of a 30-06

Thanks, and good shooting to you

[HollowPoint]

I slugged my barrel by using one of my previously cast 30 caliber cast bullets. They drop from my mold at about .311.

I just cut the cast bullet below the first driving band and file it flat there. The pointy nose guides it into the barrel and that one single driving band gives just enough resistance to get a good impression of the lands and grooves.

These were 16 BHN cast boolits. That lone driving band was thin-but not so thin that it didn't give me a good reading. The oiling of the barrel and the brass punch to get it started all still applied.

HollowPoint

[LittleBill]

Littlebill

If it ends up you have a tapered bore, could you let us know what rifle you are slugging? I understand that some makes & models have tapered bore, and your results might influence someone considering purchase of a 30-06

Thanks, and good shooting to you

I don't mind sharing at all. It is a Marlin XL7, a bargain basement rifle. The thing shoots beautifully. It has shut the mouth of one or two people who thing accuracy is a function of dollars spent, that's for sure. :D Here is my target when I dialed in the scope last fall over Thanksgiving. The last four shots were within 1", and the last three were 3/4". This is shooting off a sandbag at 100 yds.

http://i119.photobucket.com/albums/o159/FotoBill/marlinsightin_zps55e4f539.jpg (http://s119.photobucket.com/user/FotoBill/media/marlinsightin_zps55e4f539.jpg.html)


I slugged my barrel by using one of my previously cast 30 caliber cast bullets. They drop from my mold at about .311.

I just cut the cast bullet below the first driving band and file it flat there. The pointy nose guides it into the barrel and that one single driving band gives just enough resistance to get a good impression of the lands and grooves.

These were 16 BHN cast boolits. That lone driving band was thin-but not so thin that it didn't give me a good reading. The oiling of the barrel and the brass punch to get it started all still applied.

HollowPoint

A friend of mine is loaning me a .30 mold so I can cast some soft slugs to do just what you describe.

[41 mag fan]

Now this worked on my 45-70's but should apply here to with a 30cal. I took a 50cal buffalo bullet, wiped the lube off of it, and slugged my bore with it. You might try a 40 or 45 cal ML bullet. They are dead soft and work excellent.
The 50cal left a nice ring of lead at the bore when I started it and gave me excellent results with both my Browning and my Marlin.

I tried the egg sinkers thru my 300AAC. First one went with a lot of difficulty. I always do 2 to get a standard deviation on readings, but my second one got stuck 3-4" down the barrel. Took me forever to get it out.

[LittleBill]

I finally got the time and a chunk of appropriately sized lead to slug the hind end of my barrel today, so when I was done working for the day, I started in. It slugged right at .308, all the way around, and very even compared to some of my more expensive handguns. [smilie=1: So if I am correct, sizing boolits to .309 should be perfect. Would .310 be better, worse, not needed?

[wallenba]

I finally got the time and a chunk of appropriately sized lead to slug the hind end of my barrel today, so when I was done working for the day, I started in. It slugged right at .308, all the way around, and very even compared to some of my more expensive handguns. [smilie=1: So if I am correct, sizing boolits to .309 should be perfect. Would .310 be better, worse, not needed?

Hard to say. Some will do just fine with a .309, others want more. Sizing at .310 would be OK either way, and you may find another rifle some day that needs .310. You could of course, just get both sizing dies. Lee make a .309, not sure about a .310, but you can buy two 309's and carefully lap one out to .310. If I was on a budget, I'd try the .309 Lee. If it doesn't work, open it up. If you have an RCBS or Lyman lubrisizer both sizes are available in H&I types.

[NSP64]

Try some at .309 and some at .310.
see what the gun likes.
I have a savage that likes .310

[LittleBill]

I bought a Lyman lube sizer, so dies will come from them. I don't mind going to .310. All I need to do at this point is find a mold. :roll: I actually HAVE a mold a friend of mine loaned me. It is a Lyman, single cavity 155 gr or something like that. BUT, he neglected to send along the handles. :( And he is far away enough that it is a debate as to what to do about that. Do I just buy handles for a mold I don't own, or do I make the trip to see if he has any he can spare from his other molds? It is a dilemma.

[runfiverun]

310 would scuff on chambering.
depending on the boolit design and what you plan on doing with it the nose portions diameter would be more important than the body.

[Silverboolit]

Little Bill...If you would like, I could send you some 175 gr that I have sized to .310. They are a bore rider and work well in my .308. PM me if you want.

[Boyscout]

I cast a couple of .358 158 gn tumble lube bullets with pure lead and worked them down in a vise. I then slugged my Mosin Nagant with one after lubing the barrel with Break Free.

[CAVEMTNMAN]

I buy bore slugs from LBT, they have a little teat on them that fits into the end of your cleaning rod and you just put some light lube on them and push them through.