I have a 458WM that has stopped grouping.It would only group Hornady and Woodleigh RNSP when it was new.I heard that many CZ's like mine were overbore.That could explain the poor grouping with other bullets.Right from the start,it would not group monometals at all.I have not shot with it in a few years and will probably rebarrel it sometime.Now that I have all my casting equipment I was thinking of getting a mould that would cast a little larger than the standard diameter.I've slugged the bore a few times and measured with a dial caliper then compared that bore with a new one but it is difficult to get precise measurements.
Do you think a .460 mould would be too big? Some of the jacketed bullets I measured are .4555-.4565-.4570.

A .460 Cast bullet would likely NOT be too big. .002 over groove is the standard "good" in Cast bullets so should work. Now if that mould will drop a .460,
will it fit in the Case, Throat loading and shoot well; that is all to be determined. Give it a go!

so what is the bore and groove diameter?
how big and what shape is the throat?
will a 460 or larger bullet diameter even chamber?


I have heard of many 45 cal rifles taking up to .464 to get to shoot well.
but the throat shape and diameter will determine if your cast bullet will even chamber.

You are just guessing until you actually slug your barrel and measure it.
Use a 50 cal lead ball and smack it into the muzzle with a plastic hammer.
Them measure it. After you carefully remove it of course.

I slugged it again a couple of times today.I got better results this time.Both slugs seem to give maximum diameters of about .4610.

quote:

Originally posted by shootaway:
I slugged it again a couple of times today.I got better results this time.Both slugs seem to give maximum diameters of about .4610.

Problem as others have pointed out is that a .461" or .462" sized cast bullet when seated in the case neck may expand it enough to prevent chambering, just depends on how tight your chamber throat is.

Do a chamber cast so you can measure this. If you purchase a mold that throws a .461-2" bullet then you can always size the bullet down to suit what your chamber will allow.

Thank you all for the info.There are two moulds that I am interested in trying at the moment.
My goal is to make some accurate rounds with low recoil so I can have fun shooting them offhand at targets.

The first mould is from Lee Precision.
https://leeprecision.com/mold-sc-459-405hb.html

The second mould is from Accurate Moulds and has a space for a gas check.Would a Hornady 45 cal gas check fit? Do I really need a gas check bullet if I will be shooting light loads?
http://accuratemolds.com/bulle...bullet=46-500A-D.png

quote:

Originally posted by shootaway:
Thank you all for the info.There are two moulds that I am interested in trying at the moment.
My goal is to make some accurate rounds with low recoil so I can have fun shooting them offhand at targets.

The first mould is from Lee Precision.
https://leeprecision.com/mold-sc-459-405hb.html

The second mould is from Accurate Moulds and has a space for a gas check.Would a Hornady 45 cal gas check fit? Do I really need a gas check bullet if I will be shooting light loads?
http://accuratemolds.com/bulle...bullet=46-500A-D.png

Hopefully you will try light loads using a pistol or shotgun powder, I use 22.0grs Red Dot or Vectan AS (same burn rate) with a 400gr cast bullet in my 404 for great accuracy and surprisingly these are up to factory or full power reload POI.

No need for magnum primers or fillers with these light charges of easy igniting powder. Still have a little bit of recoil due to the bullet weight but much quieter, softer and easier on the pocket to shoot.

Will you need a gas check? Some like me find they do not get good or any results without a gas check on a big bore bullet, I get no grouping with any powder type or charge from the lightest loads at about 1300fps to heavier at 1900fps if shooting plain based but put on a gas check and different performance altogether.

You will only know by trial and error if you need a gas check on your cast bullets for your 458W.

I was thinking of trying H4895 and using the .6 of max rule.I get the feeling I am probably going to need gas checks.The price for gas checks is ridiculous.

H4895 is known as suitable for reduced loads but I've never tried it, Have tried reduced loads of H4350 at .72 of max with 400gr cast in the 404 and they work well but at 1900fps still a bit hard on the shoulder in a light gun when shooting off the bench.

Agree gas checks have got expensive, 45 cal Hornady gas checks currently retailing at NZ$110 per thousand here, that's about $102 Canadian dollars.

I have used some aluminium homemade checks that were given to me and they work as good as the Hornadys.

So I ordered both of the moulds.Not much info on the net regarding accurate loads for the 458WM with cast bullets especially without gas checks.I hope I can get my CZ 550,458WM shooting again.If all works out well I will consider getting a mould for my 450NE.

That Lee mould is a hollow base mould, usually meant for soft lead and slow speeds. You will just have to see like every other cast shooter. It's fun though so don't worry.
I would think the Accurate Mould with a Gas Check would be a great bullet at 1300 to as high as your rifle will tolerate at 12 to 22 BHN. What alloy did you end up with?
I use both IMR 4759 and AA 2015 and they work fine for me. I do use Dacron filler as I get better accuracy with it than without it. Some folks worry about ringed chambers/barrels but I have had no issues.
Good luck!

Alloy is 92Pb/6Sb/2Sn.

Alloy should be great!

I might try IMR 4759 and AA 5749,also H4895.

I loaded the first rounds for my CZ 458WM.

I used 50grs H4895.They chamber and feed fine in the rifle.I am using the .6 rule with max H4895,458WM loads.This should give velocity around 1300fps.I can't wait to see if accuracy will be restored in the CZ.I measured the sized bullet and got around .4605.I cleaned my CZ and looked down the bore at the rifling.The rifling was always faint in that bore.I should have results to post after this weekend.This round was loaded with bullets cast from the Accurate Molds mold-the 500gr gas check .460 mold(460-500BG).

[URL= ]458WM[/URL]

To my surprise it worked.Here is the target.The four shot group on the left was shot at 50yds and the three shot group on the right was shot at 100yds.I also shot a few rounds offhand.Feeding could be an issue not sure yet.It could have been better if the mold was round nose.Also I am going to need a higher front sight-I think I have a CZ sour dough or partridge front sight I have not used.

[URL= ]50 and 100yd target/off the bench/open sights[/URL]

[URL= ]sour dough/partridge front sight[/URL]

Great on both the results and that front sight. I covet it I must confess.

I have used my CZ 458 Win Mag to shoot about 200 cast rounds so far.Here is a target I shot offhand at 50yds yesterday.My partridge front sight still needs a little more filing to bring up the POI.I have so far raised POI about a foot.The barrel got very hot as I fired all 50 almost non stop.

[URL= ]50yds offhand with both arms extended[/URL]

Isn't cast great in the wonderful 458 bore?

quote:

Originally posted by Fury01:
Isn't cast great in the wonderful 458 bore?

The most fun I've ever had shooting!

And any of those bullet holes would have killed a deer with that bullet at that speed. Cast in the 458 is great fun, great practice and great hunting. Enjoy.

I wonder how far I can push these.I am going to try them with heavier loads.

If you are loading to the 1300fps level use of a pistol or shotgun powder e.g. Red Dot or Unique will give you that performance at slightly less recoil without using larger charges of slower rifle powder such as your H4895. Your barrel won't heat up as much with less powder being burnt.

I would guess that you can get to 1700 1800 FPS without much problem. Maybe more but not much to gain from doing so. I use 51 grains of AA2015 to get there in my .458 Win Mag.

quote:

Originally posted by eagle27:
If you are loading to the 1300fps level use of a pistol or shotgun powder e.g. Red Dot or Unique will give you that performance at slightly less recoil without using larger charges of slower rifle powder such as your H4895. Your barrel won't heat up as much with less powder being burnt.

Thanks eagle,I got some Unique on hand and will try it out.
How many grains of it did you use? I am thinking of trying 25grs.

quote:

Originally posted by Fury01:
I would guess that you can get to 1700 1800 FPS without much problem. Maybe more but not much to gain from doing so. I use 51 grains of AA2015 to get there in my .458 Win Mag.

Thanks for the tip.

I shot 5 rounds loaded with 26grs of Unique.I did not remember that I had loaded them and shot them after I shot a whole bunch of rounds loaded with H4895.The recoil was smooth and there was no fireball or flash like I get with some shots.
The reduced loads of H4895 are very dirty too but they are accurate.I did not record the accuracy of those loaded with Unique.I will load some more and use a marker to mark them as such and try them again.

You're doing very well. Accurate makes a good mold, but he will not cut a meplat smaller then .180. He could have a lot better designs if he would. The flat points are good for hunting though. His excuses for not cutting more pointed bullets is not valid. I own a few of his mold and they cast good bullets. He tends to cut on the larger side even if you specify the alloy.

quote:

Originally posted by vzerone:
You're doing very well. Accurate makes a good mold, but he will not cut a meplat smaller then .180. He could have a lot better designs if he would. The flat points are good for hunting though. His excuses for not cutting more pointed bullets is not valid. I own a few of his mold and they cast good bullets. He tends to cut on the larger side even if you specify the alloy.

That is good to know,vzerone.Thanks!

quote:

Originally posted by shootaway:

quote:

Originally posted by vzerone:
You're doing very well. Accurate makes a good mold, but he will not cut a meplat smaller then .180. He could have a lot better designs if he would. The flat points are good for hunting though. His excuses for not cutting more pointed bullets is not valid. I own a few of his mold and they cast good bullets. He tends to cut on the larger side even if you specify the alloy.

That is good to know,vzerone.Thanks!

I thank God that we have Accurate and other mold makers. There's not a lot of them.

We also have NOE molds and Mihec molds which are in Slovakia. Don't let that distant worry as I've seen a friend get molds from him in one week!!!!!!! Miha, his name, is one of the best machinist I've ever seen. Here is his link:

https://www.mp-molds.com/e-shop

Here's NOE:

http://noebulletmolds.com/main/

I shot a few rounds loaded with 35grs of Unique.I did not chrono them but they shot much higher than my H4895 loads and hit broadside.I think I will try 25grs of Unique again.

Cast is all you are ever going to need with that caliber! Don't buy those expensive jacketed bullets. Wait till you start hunting with that caliber and the cast. A little note if you push the cast really fast you will ruin a lot of meat.
45-70 velocities (the old Trapdoor velocities) is all you really need for hunting.

I shot this group today at 50yds shooting offhand.I was using 45grs of H4895.So far the casting is working great with my CZ 550 458WM.
The barrels cleans easy with these cast bullets.I must have shot close to a thousand of them so far and the barrel has gotten very hot often.I am using almost 100% pure beeswax as bullet lube.I 've got just a little olive oil mixed in.

[URL= ]50yds/offhand[/URL]

I love shooting my 458WM with cast bullets.Here is another target I shot offhand at 50yds this morning.
[URL= ]50yds/offhand[/URL]

The barrel got very hot shooting that group above and I could barely hold the forearm with my left hand.

It will be interesting to see what this rifle shoots like after I cleaned up the throat of carbon.

I've a Ruger #1 in 45/70 and upon slugging the barrel is that the throat starts almost right where the chamber ends towards the throat. Second is that my barrel is .459 So standard 45 rifle bullets are just being wasted. I'm going to accurate Molds and get about a 450 grain gas checked bullet mold that will cast .463gas checked bullet. Another thing I learned is there a restriction in my barrel. Actually two of them in fact.One is where the barrel band sling swivel is located and there is a second one where the front sightbase is located.With a very tight patch on a jag you can feel both of them. Please excuse my bad spelling as I had cataract surgery last week. One more to go. Frank

quote:

Originally posted by Singleshotlover:
I've a Ruger #1 in 45/70 and upon slugging the barrel is that the throat starts almost right where the chamber ends towards the throat. Second is that my barrel is .459 So standard 45 rifle bullets are just being wasted. I'm going to accurate Molds and get about a 450 grain gas checked bullet mold that will cast .463gas checked bullet. Another thing I learned is there a restriction in my barrel. Actually two of them in fact.One is where the barrel band sling swivel is located and there is a second one where the front sightbase is located.With a very tight patch on a jag you can feel both of them. Please excuse my bad spelling as I had cataract surgery last week. One more to go. Frank

Will this be your first time casting?