View Full Version : .45 acp with 700x
June 12, 2009, 01:02 AM
Hi, I hacve been trying to find some loading data using IMR 700x powder with a 185 gr lead SWC, however everything I find is for a jacketed bullet. What should I do to compensate for the difference in the bullet, or is anyone familiar with this combo? Thanks
June 12, 2009, 06:54 AM
Try handloads.com and hodgdon.com. I've used those databases for research and comparison. Lee's Modern Reloading 2nd edition has a lot of info on reloading lead. Unfortunately I checked mine but did not see the combo you are looking for. I was always told when lead data is not available use jacketed and reduce that load by 10%. I reload my 45acp using 230gr Berry's round nose copper plated w/4.5 gr of 700x.
June 12, 2009, 06:59 AM
Welcome to the forum.
The answer depends on what sort of velocity range you are looking at? Most 185 grain lead SWC's are for target shooting loads that are pretty light. At .45 ACP pressure levels you will find 700X and Tightgroup loads are usually within 0.1 grains of each other (less than the consistency of a powder measure) and can be interchanged without risk if they are not at maximum pressure (21,000 psi for .45 ACP standard loads and 23,000 psi for .45 ACP +P loads).
Most loads you will see are under 18,000 psi. In that range lead and jacketed load are not very different. The lead will typically produce less pressure in that load range just because it slips out of the case more easily and requires less pressure to be swaged into the bore and engraved by the rifling. As a result, the recoil also feels softer. Some of the magnum revolver loads are another matter, and Skeeter Skelton and Elmer Keith both (IIRC?) found higher pressure signs with lead working with those. The cause isn't known to me other than having heard speculation about obturation of the forcing cone being involved, but nothing that has been proven to be a certain explanation, AFAIK? It could be as simple as the lead bullet designs with large lube grooves seating deeper into the case. But watching for pressure signs is something the handloader always has to do anyway, so don't try to skip out on that.
One thing to watch out for in the .45 ACP and any other short case is that, unlike a big bottleneck rifle case, seating the bullet incrementally deeper will quickly reduce the percent of volume available for the powder to burn in by a significant amount. That increases pressure. A load that is 18,000 psi with the bullet at its correct seating depth will increase to 23,000 psi just by pushing the bullet 1/8" deeper into the case. When you load a bullet with a blunt nose, the COL is shorter because of that shape, but what actually matters is how close the base of the bullet was to the bottom of the case inside. That's what determines the powder burning volume at the start of combustion. If that matches and the bullet material and weight matches, then you will get close to the same pressure performance from two different bullet shapes.
The above is also where the crimp is important. The taper crimp usually used with .45 ACP these days should cause the case mouth to dig into a lead bullet slightly. That forms a jam against the bullet being pushed deeper into the case by recoil or by being pushed up the feed ramp and into the chamber. That crimp is therefore necessary for safety.
If you have a standard form LSWC that is seated with the base about .35" into the case when the case is 0.898" long, then around 3.7-4.0 grains of 700X will give you a target velocity of about 750 fps from a 5" tube. If you are shooting a 1911 style gun, you may have to change the recoil spring from the standard 16 lb spring down to a 14 lb or even a 12 lb spring to function with the lightest target loads. Sprinco.com (http://www.sprinco.com/springs.html) is a source of good quality recoil springs in different weights.
If you are looking for loads closer to commercial hardball muzzle energies, you will be loading that light lead bullet with about 4.8 grains of 700X.
June 12, 2009, 07:08 AM
I have shot a lot of 700X in pistol calibers and it does ok.
The main thing to be aware of is that 700X is a large flake powder and does not meter well in small charges. If you get under 4 grains for midrange target loads you must be especially sure that each case contains a correct load before you seat the bullet. I never had a zero powder "squib" but a couple of one grain charges really caught my attention. I quit using 700X in .38 Special for that reason and am very careful in .45 ACP. I have the Cowboy Trick of a cheap aquarium air pump strapped to my Dillon powder measure to settle the flakes in the powder bar.
June 12, 2009, 09:07 AM
Thanks unclenick for the great info, I loaded up some using 4.5 gr but haven't been able to shoot yet today. But you mentioned the depth of the bullet seat. When I loaded the bullets I set them so that if on a flat surface the SWC's flat nose would be at the same height as a regular commercial round nose. Is this a bad idea?
June 12, 2009, 09:30 AM
If they are sticking out that far they may not chamber or feed properly. If you measure the bearing surface (the cylindrical portion of the bullet that is the full bullet diameter), it is pretty common practice to leave the last 0.020" of that sticking out of the case mouth. However, the method I like better is to use the gun's barrel as a gauge. I'm going to guess that if you have a typical LSWC profile bullet, your load will be like the right-most position, and they won't chamber easily. I use the third from the left as it headspaces on this kind of bullet which gives best accuracy and reduces leading.
OK, where were you when I was carefully machining an eccentric weight for a little DC motor for my Dillon powder measure? Fishtank pump would have saved me a lot of bother. ;)
June 12, 2009, 02:19 PM
I have used 700X in my 38 and 45 and all my pistol loads except the 45 colt.
my load is 3.6 in AMT Longslide as issued and the same in My AMT hardballer.
issue spring.I have used that load for 20 ys before that I used 3.2 but when I did a tightning job on the FED ornance gun I had to increase it to 3.6 to funtion so I left it that way.I use a Lee 1000 for 45 and an RCBS green machine for 38,just converted that to lee measure.much better.I do use 200 gr SWC in 45.:rolleyes: :D
June 12, 2009, 06:05 PM
As mentioned, hodgdon.com is a good place to start.
They do have listings for 700X using lead bullets. That is where I got my data from for my .45 acp using 700X and 230 gr RNL bullets.
I use 700X for .45 acp, .45 Colt, .38 Special and .357 Magnum reloading.
June 12, 2009, 11:15 PM
I load Plated Ranier 185gr flat nose bullets with 4.6gr of 700X and get great accuracy out of them. Since the plated bullets are supposed to be loaded around lead data, I would say 4.3 to 4.6gr would be a good place for you to start.
June 13, 2009, 09:20 AM
A bunch of guys at my range load their 45's with 200gr SWC with 700x @ 4grains. Seems to have worked well for them over the years, so thats how my dillon is set up as well. Good luck Be safe, have fun.
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