1000 fps loads in 44

[tackdriver]

I am working up loads for my new Model 69 with a 4.25 inch barrel and my Lyman manual is giving me fits. Specifically, I am looking for weights for Unique to push 215 and 240 grn hardcast at 1,000 fps

For the lighter bullet, the manual says 10grn = 930 fps and 13.2grn = 1221 fps out of a 4-inch bbl

For the heavier bullet, the manual says 10grn = 937 fps and 11.7 grn = 1133 fps

I know you don’t push a heavier bullet faster with the same powder.

My math gives me 10.8 grains to push the lighter bullet at 1k and 10.9 to push the heavier one. This doesn’t make sense either.

 

[black mamba]

Load some of each bullet up with 10½, 11 and 11½ grains and see which is the most accurate. 30 or 40 fps one way or the other won't make any difference, but accuracy will.

 

[FrankenMauser]

Check the COAL for those loads. Consider nose shape.
They're likely different.

Case capacity matters when it comes to pressure, and bullet style and seating depth directly impacts usable case capacity.

 

[tackdriver]

Check the COAL for those loads. Consider nose shape.
They're likely different.

Case capacity matters when it comes to pressure, and bullet style and seating depth directly impacts usable case capacity.

OAL is identical in the manual. The heavier bullet is a rnfp vs lswc for the lighter round. I’d love to see some other published load data.

 

[Unclenick]

There are several reasons for what you see. First, the gun used by Lyman to test the 44 Magnum is a universal receiver. This means the barrel was a SAAMI standard velocity and pressure test barrel. The barrels have chambers that are SAAMI minimum size (tight) within a plus half thousandth tolerance. This is done so the worst case high pressure will be developed and every gun that is not that tight will produce lower pressure. Production guns are not that tight except by happy accident, so you can expect pressure and therefore velocity not to be as high in one.

Second, it is universally true that the heavier a bullet is, the more efficiently it converts the chemically stored potential energy in the powder to actual kinetic energy in the bullet. This is so even if the pressure is the same because it gives powder more time to complete burning so more gas is made by the time the bullet clears the muzzle, increasing average pressure. This makes it look like you are getting some free velocity if you base the computation on the powder energy density alone.

Third, the pressures were not the same. The .44 Remington Magnum has a copper crusher maximum average peak value rating of 40,000 CUP. The Lyman maximum load pressure for Unique with the 210 grain bullet is 36,000 CUP and for the 240 grain bullet is 37,900 CUP, or 5.3% higher. Why? And why aren't either of them 40,000 CUP. The answer is explained in Hodgdon's printed manual. It depends on how much variation there was in the pressure readings when they tested the developed load. The wider that range, the lower the pressure they choose for the maximum in order to avoid some loads going higher the SAAMI standard allows for (which is not zero variation, by the way, but there is a limit to the standard deviation of it; 5% for handgun cartridges and 4% for rifle). Some of this is excessive caution in my personal view, but it errs on the safe side because some handloaders are not as competent as others.

 

[44 AMP]

My math gives me 10.8 grains to push the lighter bullet at 1k and 10.9 to push the heavier one. This doesn’t make sense either.

It's not just a straight ratio math problem, there's more to it than that, there are other factors involved.

What I can tell you, is that EVERY gun is different. A little for most, a lot, for some. And, I can tell you that if you aren't using a chronograph, you don't know for certain exactly what velocity you are actually getting.

And, here the real kicker, IT DOESN"T MATTER!!

If that sounds clear as mud, its because it is.

Firstly, there is a range of results you will get, even with the most carefully identical components. This is where the terms "standard deviation" and "extreme spread" come in. Each shot, even with ammo as identical as we can make it will not give exactly the same velocity. There will be variance.

Second, another variance comes from firing in different guns. Even guns as idendical as possible will show differences. Sometimes it is small (and we like that) but sometimes it is larger. A difference of as much as 100fps is not common, but its not unheard of.

This is why I say it doesn't matter. IF your measured speeds are identical to published data, it is serendipity. Published data is a guideline, only. I used a chronograph and tested a wide variety of guns and loads, and found that my results were what the manuals said, allowing for the plus or minus of individual gun barrels.

In other words, don't sweat it if you get 970fps and the manual says 1000. likewise, if you got 1070 instead of 1000 with x amount of powder and Y bullet. You can "calculate" what you ought to get, but you won't know exactly what you do get, unless you measure, but for most things a handful of fps makes no practical difference.

 

[T. O'Heir]

What the manual says applies only to the exact components, firearm, if there was one, and atmospheric conditions on the day of the test only. For instance, if they tested with a 4" barrel, that you don't have, velocities will be different.
There are no published Unique loads that will drive a 240 grain cast bullet to 1,000 FPS. All loads tested are out of longer barrels and the fastest is with Red Dot at 905 FPS.
Have a look here at the 4" and 4.875"(that's 7/8" longer) barrel velocities for the Federal 240's. http://www.ballisticsbytheinch.com/44mag.html
With 2 bullet weights you work up a load for one of 'em at a time. There's no comparing powder amounts to velocity between 'em.
"...My math..." There is no math.
"...For the heavier bullet..." Alliant says the MAX load of Unique for a cast 240 is 7.0. Velocity doesn't matter as they used a 7.5" barrel(really daft test length), but it was 899 FPS. 10 grains is way over max. It's .1 over minimum for a cast 225. No 215 data given.

 

[buck460XVR]

There are no published Unique loads that will drive a 240 grain cast bullet to 1,000 FPS. All loads tested are out of longer barrels and the fastest is with Red Dot at 905 FPS.

Am I missing something here?

My Lyman manual shows the same load/velocity as the OP states......11.3 gr of Unique with a 158 gr Hardcast for a velocity of 1133fps. This from a 4" test barrel.

 

[Pathfinder45]

Well, If you have a chronograph, and you want loads right about 1,000 fps, then I think you are likely to achieve that closer to 9.0 grains plus or minus a half grain. I would start testing at 8.0 and work up from there. To some degree, it's all just numbers, but you may be wanting to stay sub-sonic, perhaps? I would stop at the most accurate load that comes reasonably close to your goal.

 

[tackdriver]

Thanks, everyone. I don’t have a chronograph or even one to borrow. Maybe for Christmas.
I learned some here!

 

[mrdaputer]

I use to go for a certain fps. I now go with what my guns likes as far as recoil and accuracy within the limits of course.

 

[Charlie98]

As an aside, I don't think my handloads have ever matched published velocities, very often nowhere near.

My standard .44SPC load is a 255grn cast over 7.5grn Unique for 900fps, out of a 5.5" Ruger. I would probably start at around 8.5-9.0grn Unique with each bullet and ease on up... stopping with the most accurate powder charge, not necessarily a specific velocity, in your 69.

 

[Pathfinder45]

Yeah, you don't really have to get a chronograph. Just start with a beginning charge and shoot for group accuracy, increasing charge weights a half grain for each set of tests until you find what works best for you and your gun.

 

[Unclenick]

I think a better rule of thumb is to work up in steps 2/3% to 1% of the maximum charge weight. 2% is OK if all you are doing is trying to find out if there are pressure signs, but that big a change can skip right past an accuracy sweet spot. Half a grain is too much for smaller capacity cases and pistol loads.

 

[Paul B.]

T. O'Heir said, "There are no published Unique loads that will drive a 240 grain cast bullet to 1,000 FPS. All loads tested are out of longer barrels and the fastest is with Red Dot at 905 FPS."

HUH! If you mean the .44 S&W Special, you're correct. However the OP is asking for data on the .44 Magnum. OOPS! I don't load Unique in the .44 Mag. but do for the Special.

I load for both cartridges and the .44 Special data is quite conservative. I've been using 7.5 gr. of Unique with a 240 gr. bullet in an S&W 624 and that load is quite safe. In fact it was the late Skeeter Skelton's pet load for his .44 Special revolvers literally from the get go.

FWIW: The now long out of print RCBS cast bullet load manual shows a start load of Unique for their 240 gr. #429-240-SIL bullet, a somewhat round nosed flat point bullet of 12.1 gr. for 1369 FPS and a max load of 13.1 gr. for 1454 FPS. Bullet is apparently design for shooting the silhouette game out to 200 meters.

Another FWIW: The Lyman cast bullet handbook #2 shows 8.5 gr. as a start load for THE 215 gr. bullet for 1015 FPS at 15,400 C.U.P. and a maximum of 12.5 for 1356 FPS at 30,000 C.U.P. Test barrel was 6.5".
Paul B.

 

[Pathfinder45]

Well said, Unclenick. I am usually working with 45 Colt. Half a grain at a time works well for me since it's a fairly large case and I want to quickly get into the ballpark and then fine tune the load from there. If I had more time for it, I would probably work with smaller increments too. With a substantially smaller cartridge that half grain increment becomes proportionately so much larger and should certainly be cut in half or so. You make an important point on this.