45 auto, Bullseye range report

M

MightyMO1911

New member
If y'all remember my post last week about the light Bullseye load I am working on, this is that report.

Gun used is a Sig Sauer 1911XO, full size non railed. Brass is mixed range brass with a 4.0 grain charge of Bullseye pushing a 200 grain LSWC. Winchester large pistol primers get it started. Also noteworthy is I have a Wilson Combat 18# recoil spring.

So last week I loaded 8 rounds and ran them across my chrono. Velocities were 744, 748, 737, 746, 730, 727, 734 and 732. The average was 737 with an extreme spread of 21 and standard deviation of 7.

All ran well in the gun with light recoil and all brass landed basically in the same spot. With these results I decided to run 20 more to determine if the results would be the same. Oh. Another note worth mentioning is last week the temperature was 55*.

Today I loaded those 20 rounds and ran them across the chrono. Temperature today is 82*. Velocities are as follows:

741, 777, 749, 762, 756, 758, 743, 758, 758, 758, 768, 754, 747, 757, 767, 774, 758, 753, 765, and 747.

Average is 757, extreme spread is 36 and the standard deviation is 9. I was impressed with these results, with 6 of them being 758. I found it interesting that the average was 20 fps faster, presumably because of the increase in outside air temperature.

This load is fun to shoot and at first glance, appears to be accurate. However, I will now load probably 50 more rounds and shoot them at paper off of a rest. I have no desire or interest in reducing this charge at all but with the 18# recoil spring installed, I wouldn't recommend it to myself either. All brass basically landed at my feet, ejecting straight up and falling straight down. This tells me I am as low as this spring and combination will accept but again, I am not reducing this load any further anyway.

This load has been a fun process and I am learning from it. It is fun to shoot and I am interested to see how the accuracy test works out when I get there.
 
(:D I published my own range report one minute after you posted this one.)

4.0gn Bullseye under a 200gn LSWC is something of a classic. There's lots of shooters loading target ammo right in this neighborhood. You are well into tried-n-true territory with these.

My 45 ACP range shooter is 5.0gn W231 under a 200 LSWC - 778 f/s. I also load it at 4.6gn, but I've never chronoed that particular loading. Similar, at any rate. My plan is to turn these down, using a lighter spring. But that's down the road. 45 ACP isn't my focus right now.
 
Well I guess great mimds think alike and do the same thing on a nice day. :) It's hard for me to believe I actually stumbled upon a "classic"all by myself and by accident. Lol. That just doesn't happen to me. Now if you will excuse me, I am off to read your report.
 
Mentioning that reminds me I wanted to ask. What is generally considered a good standard deviation? 15? Under 10? And I suppose it is all somewhat subjective given the error factor of the graph. Mine is accurate to 1% which I guess at 750 fps is pretty good at 7. But anyway. Generally speaking.
 
What is generally considered a good standard deviation?
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Good question. Hard to give a sharp, delineated answer. The lower, the better :p

I prefer my 38 Special target ammo to yield SD's at least under 15 or so. And single digits please me nicely - as are some of my target shooters.

I've got a number of 45 ACP loadings that run in and around 10. My best all-time round in terms of SD was a Hornady 230gn JFP with 5.6gn W231 under it that consistently ran SD's in the 5 or 6 range. But. . . Hornady found out I was extremely happy with its outstanding performance, so they promptly discontinued it. Hornady #4513 - darn good bullet. I still have 43 loaded but unfired specimens of these. I don't really want to shoot them :(

I digress. It seems as rounds get hotter, SD's increase. I don't expect SD's in the 10 neighborhood with 357 Mag rounds, for instance (but I do have a 158gn using HS-6 that is under 8). If 158's are in the 'teens, I'm good. If 125's are in the low 20's, I'm good. Yes, heavier bullets tend to have lower SD's. I like heavy bullets.

And I have no idea what happens in the rifle world.
 
How are you measuring your Bullseye?
Weighing?
Metering?

I once had a batch of .45 auto Hornady FMJ-CT that had an extreme spread (not SD) of 10 fps for 5 shots with VV N310, granted not a big sample, but that was the best I've seen of any of my loads in any caliber. Those were charges metered from my 10X and sorted brass (CCI).
If you really want to tighten up those number, which are pretty good BTW, try sorting your brass.
 
I use an RCBS Uniflo so I assume that is metering? I am rather meticulous about setting it up and ensuring the balance scale reads level, but I must confess I do not weigh every charge. I do, however, weigh one out of 5 and if any charge just feels wrong, such as if the drum doesn't rotate smoothly, like a flake might have gotten between the drum and cylinder, I dump that charge and throw another. No it is not a perfect system but with the equipment I currently have at my disposal it is about as good as I can get it.

This entire process is just fascinating to me and while it causes me to scratch my head at time and say HUH??!! I am enjoying it thoroughly. At some point I will add a digital scale and a powder trickler.

I also can't help but wonder what the margin of error is. My graph is accurate to 1% and at 750 fps that is 7.5, but since that is +\- it could be a 15 fps swing. But every shot is accurate within 7.5 and I think that is good enough for what I am doing. Wow I just went the long way around the barn with that one. For those of you who stuck it out till the end, much obliged.
 
I use an RCBS Uniflo so I assume that is metering?
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Yes.

but I must confess I do not weigh every charge.
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I use a 30 year old RCBS Uniflow. Works great. The only time I weigh every charge is if I'm doing a chronograph work up. Sometimes, I do a "production round" chronograph test - where I chrono 30 rounds of ammo I have loaded with a regular production process. So I know what I have with "real world" ammo. This is usually the case with ammo I'm going to take to a competition and may be subject to pass a chronograph test.

When I load a batch of 100, and once I get my Uniflow calibrated, I weigh #'s 1, 2, 3, & sometimes 4. Followed by #'s 20, 50, 80, 99, & 100. That's pretty typical. I virtually never run into any variance that gives pause (barring Unique lol). Most powders, coupled with a meticulous process and quality powder hopper, meter plenty consistent. +/- < -0.1 grains on a regular basis.
 
No need to weigh every charge if you have a good measure and a powder that cooperates. 1 in 5 is plenty, I weigh just 3 or 4 out of 50, but visually check every charge.
I think it helps to flush about 15 charges through the measure before you start, to eliminate any settling, especially with the flake powders.
 
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