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andym79
12-28-2011, 06:10 AM
I know it varies depending on lead hardness and barrel length but generally how fast can you push a cast bullet without a gas check, 1400fps?

ku4hx
12-28-2011, 07:41 AM
I know it varies depending on lead hardness and barrel length but generally how fast can you push a cast bullet without a gas check, 1400fps?

One of my favorite loads for .44 Magnum is a Lyman 429421 [non GC] boolit over 22.0 grains of 2400. Out of my Ruger Super Blackhawk 7.5" it clocks at an average 1,611 fps at 10' from the muzzle.

Thousands of rounds over the years and if there's been any leading it's been far to slight to be concerned about; accuracy was always excellent. The boolits were mostly Lyman's original #2 formulation, but I think you'll find hardness a tertiary factor when it comes to leading with proper fit and lube being more important variables.

andym79
12-28-2011, 08:08 AM
On the point of a proper fit, a .30-06 is truly a .308 calibre right! I have bee advised by some of the guys at the range to size .311 cast bullets down to .309! Would using .309 rather than .308 projectiles result in a better fit or smaller group?

As to lube, I have been using the lube that comes with the lee sizing setup! How do people find this? What better alternatives are out there?

I don't really want to have to gas check the bullet.

I have been advised to cast a .311 bullet, size it to .309 and behind load it with H4895 29grns for approximately 1700fps! Does that sound right, I am reluctant to use non published data!

44man
12-28-2011, 08:32 AM
I know it varies depending on lead hardness and barrel length but generally how fast can you push a cast bullet without a gas check, 1400fps?
I use PB to 1631 fps all the time, have taken them to over 1800 fps and there are some here that have gone much higher in rifles.
I even took them to 55,000 psi in the .454.
Those are just water dropped WW boolits.
Do a search here on lubes, I hate LLA. There is Felix, my favorite, speed green, White Label lubes, LBT lubes. To me, anything is better then Alox although some here use it just fine, I just can't. :oops:

ku4hx
12-28-2011, 08:37 AM
Yeah, a .30-'06 is .308" generally. But manufacturing processes are not perfect and you do get smaller and larger bores. I have one old gun whose bore diameter is not consistent the length of the tube.

You can't very often equate the cast boolit diameter you need to that of most jacketed bullets. You need to slug your bore, maybe at both ends, and size your cast boolits accordingly. I find .309" works well most consistently but on occasion .308" has worked too. You have to experiment with your hardware to find out for yourself.

Generally it's best to use a GC on those boolit styles that call for it. You don't have to but you may find lube in the GC groove gets into the powder. I find it pointless to try to use a GC on a non GC boolit style. I have GC molds; I just use them.

As to casting a .311" boolit, you may be able to quite easily if the mold cooperates. As-cast diameter is a function of many factors: specific alloy, mold cavity diameter, casting temp. and others I'm sure. You'll need to experiment. Casting as a craft is a hands-on activity. You need to read all the stickies here and everything else you can get your hands on. But there are few, if any, fixed formulas for success. Every caster is different and so is every gun. You have to do the work to find out what works for you.

If you want published data for cast boolits then you need to get Lyman's casting manual and their loading manual. Lots of good data in both. Lee also has a load manual.

For lube alternatives, search this forum and visit the boolit lube section.

Bret4207
12-28-2011, 09:01 AM
On the point of a proper fit, a .30-06 is truly a .308 calibre right! I have bee advised by some of the guys at the range to size .311 cast bullets down to .309! Would using .309 rather than .308 projectiles result in a better fit or smaller group?

As to lube, I have been using the lube that comes with the lee sizing setup! How do people find this? What better alternatives are out there?

I don't really want to have to gas check the bullet.

I have been advised to cast a .311 bullet, size it to .309 and behind load it with H4895 29grns for approximately 1700fps! Does that sound right, I am reluctant to use non published data!

Pardon me for being extremely blunt, but your friends are idiots as far as cast goes. You need to send a few evenings reading through the posts on boolit fit here and then star at square one and work your way forward. You have no idea what your barrel specs at, might be .308 groove with a .300 bore, or it might have a .302 bore and .310 groove or any combination you can think of. Most of my 30 cals get boolits sized .311 or .310, I almost always use the GC is the boolit sis designed for it and I know that "hardness" (an ambiguous term) has little to do with whether or not you need a gas check.

Start at the beginning friend.

parson48
12-28-2011, 09:32 AM
I shoot a 158 gr. gc in my .357 maximum. I don't own a chrony, but based on data posted by others it should be in excess of 2000 fps. Leading is not an issue. I'm not as experienced as many here, but it seems to me that proper fit trumps most other factors.

williamwaco
12-28-2011, 02:44 PM
I can push .30 cals to 1900. and .357s to 1600+.

In the past I had some loads at 2100 in the .30-30. I didn't record results back then like I do now
so I don't include them in my results.

I have some loaded to 2100 right now but the range is to crowded they will not let me set up my chronograph until the crowds die down next week.


For actuall test results see the .357, .30-30, and .38-55 loads on this page:

http://www.reloadingtips.com/pages/exp_111201a_lla_test.htm


Other users are reporting up to 2600 on this forum. I can't verify those numbers but I also can't find any reason to disbelieve them.



Happy and Prosperous New year.


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btroj
12-28-2011, 02:54 PM
Bret is spot on.
Find someone who actually knows what they are talking about and get info from them.

Sizing a bullet to .309 and shooting it at 1700 may well be a good recipe for leading. Massive leading. I is the kind of garbage that gives people a bad attitude towards shooting cast.

I personally think a GC is a good idea once you get past 1600 fps but that is in general terms only. Some combinations allow faster with no GC, some won't go that fast. Only real rule in dealing wi this is that there is no hard, fast rule.

leadman
12-28-2011, 03:11 PM
What is most important IMO is a proper fit in the throat. This is right in front of the chamber and unless the gun is new it will be eroded from the powder gases. I have only one 30-06 that will shoot well with a .309" boolit out of 6 rifles. The rest get at least .310" with one getting .311".
A rifle is more likely to shoot well with little to no leading with a boolit that is larger than needed. A boolit that is too small will be more apt to lead and have larger groups.

As long as there is room in the neck of the chamber for the case to expand and release the boolit you should be good. You can fire a full power cartridge in your gun and measure the neck on the inside to find out how large a boolit can be used. This does not mean you are going to need that size. This will be determined by the throat primarily, bore second.

I too recommend a gas check on boolits designed for them. This eleminates one variable in your quest. If you do not have that capability right now you can try it wothout, but best results will probably be at 1,400 fps or below.

As with most things concerning firearms and cast there are always exceptions.
Now get your loads made and go out and shoot. LOL Let us know how it turns out.

Mk42gunner
12-28-2011, 04:16 PM
parson48: I'm not as experienced as many here, but it seems to me that proper fit trumps most other factors.

Very well said parson.

Most of my .30 caliber rifles do well with .311" diameter boolits, the other one likes a .313" (old H&R .30-30).

As long as there is room for the caseneck to expand when releasing the boolit, there isn't any reason to go smaller, in my opinion.

As far as lube goes, there is a whole section farther down the page on lubes that you can make or buy; I like FWFL. It isn't all that difficult to make and works very well.

Robert

williamwaco
12-28-2011, 05:24 PM
I shoot a 158 gr. gc in my .357 maximum. I don't own a chrony, but based on data posted by others it should be in excess of 2000 fps. Leading is not an issue. I'm not as experienced as many here, but it seems to me that proper fit trumps most other factors.



I believe that proper fit trumps ALL other factors.


90% of all the leading problems in my life were cured by changing the sizing die. The rest were cured by changing to any of the Alox lubes.


Happy New Year.





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1Shirt
12-28-2011, 05:57 PM
:coffee:Bret's bluntness is pure honesty and common sense!
1Shirt!

williamwaco
12-28-2011, 06:38 PM
Bret's bluntness is pure honesty and common sense!

1Shirt!



Ditto!

Plus:

The advice you are quoting is coming from people who have done a lot of reading of gun magazines.

The advice you are getting from Bret and others here is advice from people who have done lots of shooting.


Happy New Year!



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geargnasher
12-28-2011, 11:31 PM
I know it varies depending on lead hardness and barrel length but generally how fast can you push a cast bullet without a gas check, 1400fps?

Your question suggests that you are under the impression that there are general rules regarding such things. I used to try to establish general rules and guidelines for my own loading, but the more I tried to discover common trends, the fewer I was able to find.

As to your .30 caliber, first remove all traces of copper fouling, reference several sources giving data for powders whose starting charges will get you about 1200 fps and work up the load until you get near the max listed, get signs of excessive pressure, or you get extreme loss of accuracy or leading.. Then, switch to a powder whose starting charges give you about 1400 fps and repeat. You'll have the answers you're looking for, and which none of us can realistically give you.

Gear

Char-Gar
12-29-2011, 12:03 AM
I know it varies depending on lead hardness and barrel length but generally how fast can you push a cast bullet without a gas check, 1400fps?

If you must've have a number, yours is as good as any, but it means very little. Only your rifle will give you a valid number.

rockrat
12-29-2011, 12:23 AM
I shoot .313" in my O3A3 and also in my Armalite AR30. As long as I have clearance for good booolit release.

williamwaco
12-29-2011, 12:57 PM
Your question suggests that you are under the impression that there are general rules regarding such things. I used to try to establish general rules and guidelines for my own loading, but the more I tried to discover common trends, the fewer I was able to find.

As to your .30 caliber, first remove all traces of copper fouling, reference several sources giving data for powders whose starting charges will get you about 1200 fps and work up the load until you get near the max listed, get signs of excessive pressure, or you get extreme loss of accuracy or leading.. Then, switch to a powder whose starting charges give you about 1400 fps and repeat. You'll have the answers you're looking for, and which none of us can realistically give you.

Gear

Gear,

There is one general rule that is almost always applicable:

General Rule: "There are no general rules."

Derived from:
"No general statement is worth a damn, including this one."
Samuel Langhorne Clemens (November 30, 1835 – April 21, 1910)



Happy New Year to You and all your Family.




.

felix
12-29-2011, 01:45 PM
Yeah, there is one rule: Allow NO leaks by whatever means. ... felix

geargnasher
12-29-2011, 02:29 PM
Felix, that's not a rule, that's a commandment!

Thou shalt maketh thy boolits fit unto thy gun, beware them that leaketh, for then thou shalt knoweth the sorrow of leaded barrels.

Gear