Squib load for slugging barell and hardness & speed for various rifle bullets

[tygar]

OK new guy to rifle casting.

I was wondering if it is practical to use a very light squib load behind soft lead bullet, shot into water, to check bore size?

Been casting for pistol since the 70s but just started with rifle and am finding the WAGing on size, hardness & speed to be more fun than I want.

I've been a high power shooter including 1000yd & we generally start at max & work up.

I have been working on cast bullet loads mostly all GCs & since I have read that hot is not what usually works I have been starting a grain or two under max.

I have way more lino than WWs & soft so been using harder leads. 15-22 bhn. I have usually water quenched my bullets for pistol & have been mostly doing it for rifle.

I am loading for 30-30, 308, 30-06, .375 & .450 Marlin right now, but will be doing various others once I get a handle on the these.

I havn't been able to get much better than 2" 3 shot groups at 50yd & 3" at 100yd. All rifles have been peep sights so even with old eyes they are as accurate as I can get without a scope (.375 has scope). All the rifles shoot better than MOA with jacketed bullets.

SO, any help would be appreciated.

1. will squib load work (I am paranoid about driving "anything" down my barrels)
2. In general what hardness should I generally try for rifle loads(target & hunting)
3. What are the usual speed ranges I should try for in rifles. Also, which powders are the ones which usually work best. I like long range shooting. I test for accuracy at 500yds. So I figure 2-300 for the cast bullets will be my range for the .30 cals.

I know these are all "general" questions & each bullet & rifle is unique, so generalities are what we are working with now. Need some reliable starting points since I have not been doing so well.

I have been reading the posts & there is a ton of stuff to learn.

With pistol it was easy, I used WWs & water quenched for mags & air for .45 & .38 match. It worked fine but rifle is not so easy.

Thanks
Tom

[runfiverun]

the first thing you need to do is forget comparing cast to jaxketed and quit thinking the procedures are the same.

each rifle you have will of course take a different mold to reach it's potential this includes the 30 cal rifles.
they "can" take the same mold, you will have different results in each rifle.
i'm not sure what your expectations or needs are and each need will take
a different approach.
for general target type shooting a velocity in the 1800 fps range will do very well even out to 300 yds.

[Zymurgy50]

Switching from jacketed to cast will require a thorough cleaning of the barrel and 20+ shots from cast to "season" the barrel before you get any kind of repeatable results.

[1845greyhounds]

What about the question of slugging with a squib load? Those answers would be very interesting.

[mpmarty]

No squib loads into water. You will end up with a very incorrect measurement due to the lead slug compressing and expanding on hitting the water. Take a dead soft lead slug and drive it down the bore with a brass rod wrapped every so often with electrical tape to stabilize it in the bore. Use a heavy hammer and tap lightly.

[Pilgrim]

I've slugged the bore of a number of rifles using very small charges of bullseye. No reason any of the other fast pistol/shotgun powders won't do as well. Take the as cast boolit, lightly lube it by hand (oil works for a lube for this purpose), put it in a case that has a very loose neck (so you don't squeeze the boolit down), a small charge of powder (depends on the cartridge how much you use - anywhere from 1/2 grain up to maybe 2 grains for a large case), make a stack of towels or something similar at least 1 ft thick and shoot straight down into the towels. To be safe put the towels over dirt so a more energetic boolit goes into rhe dirt and doesn't ricochet into you or something else you cherish. I prefer to use too much powder at first so I don't stick a boolit in the barrel. If the boolit goes completely thru the towels, lower the charge and do it over. When you have the right charge the boolit will stop in the towels and then you can measure away.

[Harter66]

Well, I'll tell what I know and it ain't much.

Some where between 1.5 and 2 gr of Unique will do what you ask of a squib load in 30-06' w/150gr boolit 1-1.5 will probably do a piece of 00B the same way . The issue is that on impact it may swell/mushroom to a false reading.

I worked MY 06' w/ a 200gr plain base to 1200fps w/Red Dot ,1750 w/Unique and 1900 w/4350.
Meanwhile a 32 Rem (think 32 Win spcl w/Weatherby shoulders) w/a plain based 175gr 2R boolit did the same w/Red Dot and Unique but over 2100 w/4350 . I don't have the records handy but the 7x6.8 Rem is good w/o GC's to 1100 or so w/Unique.

If you really want jpj velocities then paper patching can get you there but it is another adventure all together. To offer an example I've a 170 gr boolit that is all but 'there' in a 308 over 2500 and an 06' at 2600fps but I'm still working the 06'. I've a 7x6.8 Rem that drives 130s Papered to 2250 and quarter sized 100yd groups.

For hardness WCWW will do for everything I've outlined above .

River run is right, about 60% of everything you know works for your rifles is wrong w/cast.
Get all the copper fouling out that you can it will make all the difference, leading wise. I had 3 that I just couldn't get to stop leading . All 3 had layered fouling copper over powder over copper . Discovered by a change of solvent all of the sudden dirty patches and blue and green stains on them w/the copper solvent again. now they're clean and don't foul at all. 0000 steel wool is your friend.

[w30wcf]

Tom,
Welcome to the forum. To answer some of your questions....

"I was wondering if it is practical to use a very light squib load behind soft lead bullet, shot into water, to check bore size?"
I typically check bore / groove diameters with an oversized soft lead round ball but I have also taken a light slighty oversized soft bullet and loaded it into a primed case and fired it. That pushes the bullet into the barrel where it can be easily be pushed on through with a wooden dowel purchased at Lowe', etc.. I would think that you could load a light charge of faster burning powder..... say 1 gr of Bullseye, position the powder to the back then shoot it into your bullet catcher. If the bullet does not clear the barrel, just drive it on through with the wooden dowel and measure it.

"I have way more lino than WWs & soft so been using harder leads. 15-22 bhn. I have usually water quenched my bullets for pistol & have been mostly doing it for rifle." BHN range is fine I've shot 15BHN to 1800 f.p.s. with good accuracy and 22 BHN to 2,400 f.p.s. in my .30-30's.

"I haven't been able to get much better than 2" 3 shot groups at 50yd & 3" at 100yd. All rifles have been peep sights so even with old eyes they are as accurate as I can get without a scope (.375 has scope). All the rifles shoot better than MOA with jacketed bullets. SO, any help would be appreciated."
What bullets / powders / charge weights have you tried so far?


"1. will squib load work (I am paranoid about driving "anything" down my barrels)"
See previous answer.

"2. In general what hardness should I generally try for rifle loads(target & hunting)"
12 - 15 bhn should work well for both (max velocity < 1,800 f.p.s.i.

"3. What are the usual speed ranges I should try for in rifles. Also, which powders are the ones which usually work best. I like long range shooting. I test for accuracy at 500yds. So I figure 2-300 for the cast bullets will be my range for the .30 cals."
Best luck will come without too much trouble at < 1,800 f.p.s. if the bullet fits the throat / barrel. 1500-1800 f.p.s. works fine at 300.

w30wcf

[lwknight]

Don't worry about driving a slug down the barrel.
Gun barrels are hard,tough and super strong steel.
You cannot scratch it unless you use an abrasive or tool steel.
Many rifles get 1000s of copper clad steel jacketed bullets shot through at greater than 50,000 psi pressure and still live long anyway.

[texassako]

I thought I had to slug every rifle barrel I had when I started casting. Then I did a chamber cast of a rifle because I was told on here about sizing to fit the rifle's throat and not necessarily the bore size, but the cast also has a bit of the bore to measure as well. A few taps and out it pops, no more tapping all the way down the barrel. I just thought I would throw out a different option than a squib load or a lead slug.

[runfiverun]

I thought I had to slug every rifle barrel I had when I started casting. Then I did a chamber cast of a rifle because I was told on here about sizing to fit the rifle's throat and not necessarily the bore size, but the cast also has a bit of the bore to measure as well. A few taps and out it pops, no more tapping all the way down the barrel. I just thought I would throw out a different option than a squib load or a lead slug.

this would be the correct step to take.

[303Guy]

If you do decide you want more velocity there is the paper patch option. But be aware, it is quite challenging but it's also a lot of fun.

[cpileri]

Let me also give another reason to tap w wooden dowel and not use a squib load: if you have a barrel that is not perfectly bored, that is, has a constriction or bulge of different diameter than the rest of the length, you will fel it as either a loose spot or a tight spot when tapping the slug w a hammer. If you shoot it, you miss that feedback.
C-

[tygar]

Hi, thanks to all responders.

I guess I wasn't specific enough for some. I tried to be general to get general info that people have found that works in those various calibers.

Really appreciate the stuff on the slugging. I had also thought about just using a primer & sticking the bullet but I kept reading about people always driving the bullet completely through the barrel.

I'm not driving a bullet with a metal rod of any kind down barrels that cost big bucks, for any reason.

The chamber casting is also a good idea, thanks Texas.

Pilgrim I will try your idea, plus all the others (even the water) just to see what differences I get. This will be an interesting experiment.

Harter & w30wcf(& the hardness), thanks for the load info, so far I have been using 3031, 748, 4195.

More info on specific loads for specific weights would be a help.

In the 30s I start 1 to 2 grains below max for the highest weight bullet then load the 150-180 bullets to that load & try that. The 130 has been loaded by computation since it weighs out at 139. (It actually has been the most accurate, so far)

Then I start to increase the charge in the lower weight bullets & decrease in the higher wts.

Also, the weights of bullets thrown from the molds can be way off about half have been close & half off, sometimes by a fair amount. Was making some 180s & 170s using the same pot of lead (1/2 COWW + tin & 1/2 soft lead) the 170 mold came out 168-169 & the 180 mold came out 165!! go figure - that mold is way off (lee).

I know that harder are lighter & bigger etc. but a RCBS(or Lyman) mold for .458 300gr gc, using hard lead throws 330 at .459/60. Now that's off but exactly what I was looking for as I wanted 325-350 bullets for the 450 Marlin.

So some info on what powder loads work for those weight bullets for YOU guys would help shorten the experimenting in the various wts for me.

As w30wcf says, I use wooden rods to push stuck bullets out of the chamber.

Also, I'm not equating cast with jacketed bullet shooting, but it's hard not to want to go fast.

That's why I said I have read that shooting slower is usually more accurate & that I have been starting loads below max.

What I was hoping for is some powders & loads that you folks use for those calibers that work for you. Then I could try them & see how they work for me.

I have numerous molds for the 30s. 113, 130, 150, 170, 180 (also I think I have a 190 or 200) so I think I'm covered. (I get 160 from the 170 mold with lino)

For the .458 have .300(330), 350, 405, (470 or 80??) 500. Have only cast the 330, 350, 405 & only loaded the 330 so far. So ANY loads for those would be helpful.

Run5run, I know, & it's hard not to think in jacketed terms but I'm focusing on what I'm learning & have read on here.

zmurgy, you bet, all my barrels are clean & by the time I have shot these rifles with cast for accuracy they have been shot at least that many times. I always test fire loads to see if there are any problems, pressure etc.

Marty, thanks, I forgot that water is quite hard.

Kiwi guy, thanks but I'm having enough trouble now, don't think I want to add another learning curve. lol

lwknight you are correct but again, not in my barrels. Also, you can damage barrels even using aluminum cleaning rods, that's why BR guys are so careful & gentle with them.

cpileri thanks that is a good option "if" I can drive the bullet with a wooden rod thru the barrels. Obviously not all my rifles have custom barrels, e.g. the 06 I'm shooting is a 03 with a unknown barrel (but it shoots well) so I use it. Actually I have several other 06s & can just try a different gun. hmmm

Well this is way longer than I planned. If I missed anyone, sorry, but all input has been appreciated & inputed into the old brain box.

Please send me anything else you all think of especially loads that work for you in the 30s & .450 or .458s.

Thanks again
Tom

[lwknight]

Someone on this forum warned me that a wooden dowel could split on an angle
creating 2 opposing wedges. You will really have a problem if that happens.

[tygar]

In fact I just got thru squibbing the 30-30, 30-06 & .450.

The 30-06 didn't have enough powder & the bullets didn't go far enough, the 30-30 had 2 much & went into the ground & the .450 went within 4" of the muzzle so I actually had to pound it down most of the barrel.

I was very surprised with the results. I shot the slug at .462 after lightly hitting with a hammer. The dia. after it came out was .456/7. I guess I can try both sized at .458 & unsized to see what happens.

All rounds were hard into lands & grooves when shot.

Regarding splitting the dowels, it happens with pointed jacketed bullets on occasion but I've never had a real problem getting it out. Don't think they will split much with flat nose lead.

Guess I'll increase the 06 to 1.5 grs & decrease 30-30 to .6gr.
Tom

[Larry Gibson]

Quite frankly with those cartridges I wouldn't waste my effort slugging the barrels. I'd simply use .310 or .311 preferably if the bullet casts that big. I'd size .377 in the .375 and .460 in the .450. I normally do not slug barrels unless there is an indication it is oversize. I many times will do a chamber/throat cast to ensure the bullet fits there as that is more important to get that right than knowing the exact groove diameter.

Alloys do not need to be super hard BHN wise for normal cast bullet velocities in rifles. A well balanced ternary alloy (lead, antimony and tin) will suffice at 14 - 17 BHN. The best accuracy is going to be under 140,000 RPM with the cartridges you list. That's around 1950 fps with 10" twist barrels, around 2200 fps with 12" twists of which your .30s and the 375 are probably one or the other. The 450 Marlin's twist is slow enough that you will not exceed that RPM.

Larry Gibson