.45 185gr LSWC Bullseye data - IDPA

[plan4]

I realized today that the last IDPA match of the year in my state is in less than two weeks and I was thinking about doing it. It will be my first.

I am accustomed to loading 185 gr coated LSWCs over 4.6 grains of Bullseye for general range shooting with a 5" 1911. I need to figure out what my load would be to make the 165 power factor.

I realize 185gr is not the best way to make 165 power factor, but it's what I have (a LOT of).

Looking at the Lyman guide, I see that the min load of 3.5 gr yields 678 fps, and the max recommended load of 5.6 gr yields 975 fps. In order to make a PF of 165 I need a velocity of at least 892 fps. So somewhere just south of 5.6 should be good, but how far south?

I do not have access to a chrono. Does anybody have load data for a 185 gr LSWC and Bullseye that will reliably make 165?

Before anyone chews me out for not searching, I've been looking all over the place, but almost universally if someone asks about 185gr, the thread immediately becomes a thread about how 230gr is preferable.

Thanks

Edited October 21, 2014 by plan4

[plan4]

Well, I just ordered a chronograph.

Now I have to make my way through 4000 185gr bullets...

Edited October 21, 2014 by plan4

[nwhpfan]

I shoot the crap out of 185's or 180's with BE. But I do it about 4.2-3g for a around 750FPS because I shoot ".45 minor." When I went looking for this load I started at 4.4-5 and velocity averaged 815. That's the best I can do. Good luck!

[jcc7x7]

should be able to go up to 6.0 grains and get PF

[plan4]

Thanks!

I bought a chronograph (Caldwell Balliatics) and started working my way up.

I shot some Winchester Train & Defend 9mm through my STI Eagle 5 as a reference. Under ideal lighting conditions they consistently chrono'd about 100fps faster than their listed velocity. Of course, the stated velocity makes no mention of what they were fired out of.

My concern is the possibility that my chrono is reading high. Is there a good way to check the accuracy of the chrono?

[Steve RA]

Set it up ahead of, or behind, another chrono. Should be close in FPS readings.

[tac_driver]

I calibrate using cci mini-mags out of my browning .22

if it is within +- 30 fps of the published fps on the box

then i'm good.

[zzt]

plan4, you have to be very careful when using the Caldwell chrono, and more so than other digital, light operated chronos. With any of them, the best operating scenario is to place the unit in the shade where the sun screens have an unobstructed view of the sky. Direct sunlight on the sensing ports messes up the readings- a little on my Pro Digital and a lot on the Caldwell. Additionally, if direct sunlight falls on only one sensor of the Caldwell, the unit returns wacky numbers or just repeats the last good velocity reading. You are much, much better off using the IR LED screens with the unit in total shade.

[plan4]

Two chronos in line is brilliant.

I hear you about the light. Both sessions were ideal light for the chrono. Overcast the first day and very even light with good cloud cover the second. I'm not as concerned about that because across 6 different loads in two calibers, the spreads were not unexpected.

I was/am more concerned about ensuring the unit is not consistently over reporting the velocity.

[plan4]

I'll definitely look into the illuminated shades though.

[Flexmoney]

http://www.handloads.com/loaddata/?Caliber=45+ACP&Weight=All&type=Handgun

[plan4]

Yeah. I checked handloads.com but I find most of their data questionable.

For instance, the only applicable load listed (180gr LSWC, bullseye powder) is 5.4gr yielding a velocity of 985 fps. I can only assume that they are hitting that velocity either with a 6" bbl, or because of the 1.19" OAL.

I cannot achieve a 1.19" OAL with the bullets I have. The shoulder of the bullet would be well below the edge of the case!

I don't know if this is useful to anyone else, but here's what I came up with:

Pistol: Les Baer 5" 1911

Distance to chrono: 10'

Altitude: Sea level

Temp: 55 degrees

Coated NLG 180gr LSWC

mixed headstamp brass

Federal primers

1.250" OAL

10 rnd strings

5.6gr Bullseye

Avg: 915.2 FPS

Stdev: 14.5

Power Factor: 162-169 AVG 164.8

5.8gr Bullseye

Avg: 932.2 FPS

Stdev: 4.6

Power Factor: 167-169 AVG 167.75

So it looks like 5.7gr would probably get you there, but 5.8 is the sensible load to consistently make major/IDPA CDP power.

Edited October 27, 2014 by plan4

[zzt]

plan4, the 1.19 OAL you cite is for an H&G 130 profile bullet, not the 68 profile. Think of it as a wad cutter with a little bump on the nose.

[plan4]

I figured it was. The "button" semi wadcutter. I don't know how they achieve the listed velocity. For me, that load would yield almost 100 FPS less.