Bore Slugging

[Harry]

When is bore slugging warranted? I am new to casting and reloading and am doing alot of reading on this site (great information). I have 30-30 and 30-06 rifles that I don't think have been fired alot. They were used for deer hunting for about 30 yrs and maybe had a total of 500 - 1000 rnds. fired. Also have a 38/357 S&W Highway Patrolman that has very little firing. Should these be slugged?

Thanks,

[454PB]

Most casters would say slug everything. In truth, if you get good results shooting "standard" size boolits, it's not really required. However, if initial results are bad (leading, inaccuracy) then slugging is the first step to fix the problem.

[BruceB]

Harry, a warm welcome to you!

After messing with cast bullets for quite a few years now, I find myself leaning rather strongly to the "keep it simple" school of thought. On your question of "when" to slug the bore(s), I'd say this:

IF your guns in question are reasonably modern, reasonably common, and made by mainstream makers, I wouldn't bother slugging UNLESS you encounter a problem such as very poor accuracy or severe leading.

That statement is based on my current level of experience and present methods, and one of my 'current' procedures is that I usually start out using a bullet diameter LARGER than the "nominal" figure for a given cartridge or caliber. That is, in nominal-.308 bores (.30-06, .308 Winchester, etc.) I am generally using .311-diameter cast bullets, For my four S&W .357s, I use .359" diameter. In my .45-70, I shoot .459-.461" bullets. These diameters shoot VERY well in my guns, and without leading.

A commonly-accepted principle here on this Board calls for shooting bullets that fill the THROAT of the chamber, rather than considering the groove diameter to be the critical factor. Use the largest-diameter bullet that still allows the action to close easily, (or chamber easily, in the case of the revolver) and you'll be very close to having the 'proper' diameter for that firearm.

You'll get more responses, I'm sure, but this system is working very well for me.

Again, welcome aboard.

[Wayne Smith]

Rather than slugging my 357s I simply shot boolits sized .357 and .358. They were both more accurate with .358 even tho they load a touch harder. I set my 357 sizer aside.

[mroliver77]

Myself I want to know if my barrel has tight or loose spots and the size and shape of throat(or lack therof) I dont own too many guns so it is not a problem to do throat impressions and slug the bores. Had a M48 mauser that leaded and shot just so so. I found rough and tight spots in the barrel. A quick lapping and man did it shoot and no leading. My .38 cylinder measures a loose .360 and needs .360 boolits or it leads badly. I like to puts around in the shop anyways so ...............
J

[Blammer]

Welcome Harry!

I too was wondering that same question when I started looking to shoot my 30-06.

I shot .311 sized boolits and .309 size boolits in it and it was fine. Good accuracy, no leading.

I suppose I could have stayed with my .311 sized boolits and shot good groups and been happy but N OOOOOOooo I had to slug my barrel measure the throat and do other stuff...

I slugged it and found that it was .308x.3015 with .03 freebore at .310 dia and the rifling starts at 2.79.... bla bla bla... didn't help me shoot any better but now I supposedly know what it will shoot good.

was it needed? no, just things to do sometimes...

start simple, if leading and bad accuracy then ask here and we'll help you fix it.

[Harry]

Thanks all for the input. I'll shoot some rounds when I get a chance and see how they do before going the slugging route.

Harry