Improving Accuracy, 45ACP, SIG P220, Zero 185gr, JHP

It has been a while now where I have tried to find a more accurate (smaller grouping) load for my SIG P220. I always try to better my previous best grouping load for a particular gun, but for a while I have not seen any improvement with my P220. It could be the me, gun or load, but I decided to keep on trying.

About a week ago I saw Roze had some 45ACP Zero 185gr JHP bullets available, so I ordered 1000 of them. Since then they have been sold out again.

The plan is to use this bullet to see if I can get some improvement on my accuracy. This bullet is known for it's accuracy, so at least I am removing one of the variables.

Yesterday I loaded a set of test loads, just to get a feel and see what my baseline is. I did not see any eye opening accuracy yet, but did see very consistent groupings, which is probably more attributed to the quality bullet. In another post I indicated that weather was an issue, so things were not as perfect as it could be. You will see with the last two loads that the chrono started acting up, which was due to the weather.

I now have a baseline to start from, and will start planning my future loads.

Some of you will say that my loads are a bit on the low powder side, which is true, but I planned the first load using this article https://www.shootingtimes.com/editorial/loads-for-the-bullseye-shooter/99418, and validating it against the Hodgdon load data.

All these loads performed flawlessly with no failures. These are really soft to shoot, especially with the heavier P220.

Following are my test results:

45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.4gr, FED150
Average: 653
ES: 26
SD: 9.8
Force: 175
PF: 120
Velocities: 669, 648, 654, 655, 643
Grouping @ 15yd: 1.09"
Test Date: 07/04/2022


45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.5gr, FED150
Average: 665
ES: 40
SD: 17
Force: 182
PF: 123
Velocities: 674, 687, 647, 649, 669
Grouping @ 15yd: 0.96"
Test Date: 07/04/2022


45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, FED150
Average: 676
ES: 75
SD: 28.3
Force: 188
PF: 125
Velocities: 724, 668, 649, 677, 666
Grouping @ 15yd: 1.02"
Test Date: 07/04/2022


45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.7gr, FED150
Average: 687
ES: 25
SD: 11.4
Force: 194
PF: 127
Velocities: 696, 703, 678, 678, 682
Grouping @ 15yd: 0.95"
Test Date: 07/04/2022

45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.8gr, FED150
Average:
ES: 0
SD:
Force:
PF:
Velocities: , , , ,
Grouping @ 15yd: 1.52"
Test Date: 07/04/2022

45acp, P220, 4.4"
Case: Winchester
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.9gr, FED150
Average: 703
ES: 16
SD: 11.3
Force: 203
PF: 130
Velocities: , , , 711, 695
Grouping @ 15yd: 1.02"
Test Date: 07/04/2022

Misplacedtexan said:

Try using a different powder.

Click to expand...

That is the plan. I am going to try different powders, but also retest the 4.6gr load, and maybe another one. I have some federal match primers, and maybe will try those also.

fxvr5 said:

vaalpens, nice groups. your gun appears to like that bullet/powder combination.

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Thanks for the nice comments. I will retest some of those loads, especially the 4.6 load since I think my shooting wasn't that good on the day.

Walkalong said:

4.6 Grs N-310 and a Zero 185 Gr JHP shot very well for me in a Caspian 1911 (No longer have) and my S&W 1955 Target. A little over 800 FPS from the 1911, a little under 800 FPS from the S&W revolver. 1.220 to 1.225 OAL

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Thanks for the comments. It seems N310 is what is mostly used for accuracy. I will definitely buy a pound to try out if I can find it locally. It is on my to-get list.

LiveLife said:

• TiteGroup, 4.4 gr - 1.09"
• TiteGroup, 4.5 gr - 0.96"
• TiteGroup, 4.6 gr - 1.02"
• TiteGroup, 4.7 gr - 0.95"
• TiteGroup, 4.8 gr - 1.52"
• TiteGroup, 4.9 gr - 1.02"

I think this may help.

Shooting Times evaluated various 185 gr JHPs using popular bullseye match powders to identify the most accurate loads (N310, N320; Bullseye; 700-X, Clays, Titegroup, WST and W231) - https://www.shootingtimes.com/editorial/loads-for-the-bullseye-shooter/99418

Zero 185 gr JHP was seated to 1.200" OAL. 1911 Caspian slide/frame with 5" Kart barrel was mounted in Ransom Rest and tested at 25 yards to produce 15-shot groups and here are their results:

• Titegroup 4.2 gr - 1.77" (708 fps) Fed 150
• Titegroup 4.6 gr - 1.44" (789 fps) Fed 150
• Titegroup 5.0 gr - 1.71" (837 fps) Fed 150

Your 15 yard test results being inconclusive may indicate accuracy node being overshadowed by different reloading/shooting variables. One such variable was Shooting Times using new Starline brass. (If you are using same headstamp range brass, have you conducted bullet setback test by feeding/chambering dummy rounds from the magazine? Shooting Times article mentions "Cases do shrink with repeated firing/reloading, and this affects headspace which affects accuracy")

So accuracy node identified by Shooting Times Ransom Rest test seems to be around 4.6 gr of Titegroup. And these are smallest groups produced by other powders:

• Bullseye 4.9 gr - 1.55" (826 fps) WLP
• Clays 4.0 gr - 1.49" (675 fps) WLP
• N310 4.3 gr - 1.51" (800 fps) WLP
• W231 5.0 gr - 1.28" (709 fps) CCI 300
• W231 5.3 gr - 1.22" (771 fps) WLP
• WST 5.0 gr - 1.77" (835 fps) WLP

Click to expand...

Thanks for taking the time to review my results and the comments you provided. I did read the article from Shooting Times, and that is actually what I based my starting loads on. Shooting Times actually used the Federal 150 Match primers for their test. I have some match primers, but decided to first set a baseline, then maybe refine some of the better loads. That is probably what I will do next.

I use headstamp range brass, but I sort it by length. So the 5 rounds per load should have the same length cases at least. I did my normal plunk, cycle and setback test. No setback was encountered when I did my test.

I should be able to get to the group sizes they have produced since they test 15 rounds, and I am only testing 5 for now. Anything better than a .864" group at 15 yards, should be better than a 1.44" at 25yards, in theory at least.

Looking through my load data I realized that I have another TiteGroup 4.6gr load that grouped very well. Here it is:
45acp, P220, 4.4"
Case: Federal
COL: 1.250"
RMR, 230gr, FMJRN, TiteGroup, 4.6gr, FED150
Average: 716
ES: 25
SD: 9.6
Force: 262
PF: 164
Velocities: 730, 718, 719, 705, 710
Grouping @ 15yd: 0.54"
Test Date: 06/03/2021

lordpaxman said:

I like my P220 and appreciate your efforts! I was wondering if in your quest for perfection if you had considered varying COL and still making major PF or just bullseye? The article mentions consistent and longer case lengths were an important factor as well. I’m not sure if case length would affect precision more than tuning COL.

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Thanks for the comments. I am not trying to make major or try to go bullseye shooting, but rather just trying to find the best accuracy I can get, and then try and beat my best groupings with other loads. I normally don't change the COL to try and improve accuracy, but will play with it a bit once I have load that is consistently accurate.

SingleActionAndrew said:

Have you considered testing on a target further away (at least 25 yards) and with a larger sample size (at least 20)?

N310, Bullseye and 700X (what Roze uses) are all well proven here. WST a favorite for softer loads. Titegroup in my experience is rarely part of the conversation.

As a benchmark against your loads you could buy some Atlanta Arms. For example Rock River guarantees their bullseye guns for 1.5" group at 50 yards with the Atlanta Arms match jhp (4.5gr N310, nosler 185, 1.200" COL IIRC - "The Marine Load"). Obviously that type of performance takes adequate gun, ammo and shooter.

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Thanks for the comments. I do most of my testing at 15 yards to narrow down the number of loads. Once I have an consistent accurate load, then maybe I will tinker with it and start testing at 25 yards. For me I thing the larger sample size will be problematic since it will bring more of me into play.

I am still trying to get some N310, but have Bullseye, 700X and WST. I am going to try all of them.

I like you idea of a benchmark. It is maybe something I need to do just to see how a proven accurate load will perform with my P220 and me as the shooter.

Rule3 said:

Ask Brad Miller PhD if you can borrow his ransom rest!
His articles are so wordy and full of mumbo jumbo

I mounted it in a Ransom Rest and fired a single 15-shot group at 25 yards for determining the accuracy of the handloads.

Summing it up, all the powders produced nice groups from my pistol, though some were more consistently smaller than others. The overall average of the 55 groups fired was 1.90 inches. My gun showed preferences for some powders and specific loads, which is no surprise because most guns do.

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There is a lot of mumbo jumbo, but at least he included all the loads. Sometimes you have to read between the lines. For one load he did a 30 shot group. He must have thought he had a very accurate load. For other loads he tried different primers. Probably was a favorite or accurate load, just trying to tinker with it a bit. Strangely he did not play with the COL at all per bullet.

I decided to do some more testing today after loading some more variations with TiteGroup. This will probably be it for TiteGroup for now, but I will probably get back to it after trying some other powders, just to refine or validate a couple of loads.

I did some back to back testing today with my p365X following the P220. It seems to me that the P220's trigger does not surprise me yet, where the P365X seems to transition smoother. The P220 only has 1600 rounds through it, so I don't think it is on par yet with my other older SIGs. This could probably explain why I haven't been able to get consistent good groupings out of it yet.

Here are the test results, some of them not bad at all. For the first two I had some chrono issues again, but afterwards everything went smoothly. The P220 again had no issues.

The testing was done at 15 yards, using a rest and a scope. The scope was not zeroed, which explains where the POI is.

45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, FED150
Average: 673
ES: 12
SD: 6.1
Force: 186
PF: 124
Velocities: , , 667, 675, 679
Grouping @ 15yd: 1.37"
Test Date: 07/07/2022


45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, FED155
Average: 695
ES: 23
SD: 8.4
Force: 198
PF: 128
Velocities: 694, 697, 709, 686, 693
Grouping @ 15yd: 0.59"
Test Date: 07/07/2022

45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, CCI300
Average: 694
ES: 46
SD: 18.9
Force: 198
PF: 128
Velocities: 728, 690, 684, 682, 690
Grouping @ 15yd: 1.17"
Test Date: 07/07/2022

45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, CCI350
Average: 746
ES: 41
SD: 15.9
Force: 229
PF: 138
Velocities: 741, 739, 755, 729, 770
Grouping @ 15yd: 1.11"
Test Date: 07/07/2022


45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, FED150M
Average: 699
ES: 72
SD: 28.1
Force: 201
PF: 129
Velocities: 711, 714, 690, 655, 727
Grouping @ 15yd: 0.84"
Test Date: 07/07/2022

45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.7gr, FED150M
Average: 702
ES: 21
SD: 8.4
Force: 202
PF: 129
Velocities: 702, 698, 712, 691, 709
Grouping @ 15yd: 1.27"
Test Date: 07/07/2022

Rule3 said:

My Sig P220 is the most accurate non 1911 45 I have, I usually just use the standard GI HardBall load. I have messed with other bullet weights and profiles. Nothing extraordinary
Pretty much 4.8-5 gr BE or 5.0 gr HP38

Same loads in DW 1911 and a SA XDm

Click to expand...

Thanks for the comments. The next powder I will try will be BE, HP38/W231 or 700X.

I know the P220 is accurate if I can do my part, so I probably need to do a lot more shooting to get the trigger a bit smoother.

I was surprised with the accuracy of the FED155 magnum primer. It is not my best ever for the P220, but it is up there. Here are my top 5 so far:

45acp, P220, 4.4"
Case: S&B
COL: 1.175"
Berrys, 200gr, RS, SportPistol, 5.6gr, CCI300
Average: 814
ES: 33
SD: 13.9
Force: 294
PF: 162
Velocities: 828, 795, 810, 828, 812
Grouping @ 15yd: 0.539"
Test Date: 03/04/2018

45acp, P220, 4.4"
Case: Federal
COL: 1.250"
RMR, 230gr, FMJRN, TiteGroup, 4.6gr, FED150
Average: 716
ES: 25
SD: 9.6
Force: 262
PF: 164
Velocities: 730, 718, 719, 705, 710
Grouping @ 15yd: 0.54"
Test Date: 06/03/2021

45acp, P220, 4.4"
Case: S&B
COL: 1.175"
Berrys, 200gr, RS, SportPistol, 5.3gr, CCI300
Average: 771
ES: 72
SD: 31
Force: 264
PF: 154
Velocities: 771, 796, 807, 746, 735
Grouping @ 15yd: 0.546"
Test Date: 03/04/2018

45acp, P220, 4.4"
Case: Federal
COL: 1.175"
Berrys, 200gr, RS, BE86, 6.3gr, CCI300
Average: 780
ES: 49
SD: 19.3
Force: 270
PF: 156
Velocities: 760, 765, 783, 784, 809
Grouping @ 15yd: 0.561"
Test Date: 03/04/2018

45acp, P220, 4.4"
Case: Federal
COL: 1.200"
Zero, 185gr, JHP, TiteGroup, 4.6gr, FED155
Average: 695
ES: 23
SD: 8.4
Force: 198
PF: 128
Velocities: 694, 697, 709, 686, 693
Grouping @ 15yd: 0.59"
Test Date: 07/07/2022

.45Coltguy said:

Might try Hodgdon's "Clays". Very clean, soft shooting and a very accurate powder. I've only used it with 230gr. LRN coated[T & B bullets]. It's been a good load.
Would imagine it would work rather well with those 185's.

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Thanks for the recommendation. I don't have Clays at the moment, but will keep an eye out for it.

It seems 200gr bullets are supposed to be even more accurate, especially the SWC bullet. I actually tested a very accurate 200gr SWC load, but it didn't feed reliably in my P220.

ArchAngelCD said:

My favorite 45 ACP load is a hard cast LRN 230gr bullet over 5.5gr W231/HP-38 with a CCI-500 primer.

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Thanks for sharing your load information. I don't shoot lead in 45acp, but if I try one of these days, then it seems everybody like W231/HP-38 loads.

SingleActionAndrew said:

Respectfully, I don't think your sample size (5 shots) is large enough yet to discount random chance and other factors from your results. Maybe when you shot those 5, your blood sugar or caffeine level or perhaps assumption that the primer wouldn't make a difference helped put your mind in a better place at that moment for precision shooting. More shots! I shoot bullseye and intend to be a top competitor so I may take this a little more seriously than what you're after but I used to test with smaller samples like this and soon learned what works on one day might not another. And that box of loads we're testing might perform differently because it's been sitting in the sun for a couple hours vs. the temperature at sun up, cold from the night in the garage.

Watching with great interest. Thanks & please keep sharing

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Thanks for the comments. I understand 5 shot sample sizes does not confirm any accurate loads, but I do think it helps me zone in on possible accurate loads. I normally follow up the testing with additional testing. If a load consistently results in an excellent 5 shot group, then I think I have found something accurate. This is also the time when I start testing at longer distances, to really separate the loads I can rely on for accuracy, and those I can't. I don't shoot competition, but I look at it this way. Which gun and load would I use if I have a friendly accuracy competition with a friend of family. At the moment I don't have one for my P220, but I would like to get to that.