Working up a new 9mm Production load

[JAFO]

My loa for the P226 with 124gr Zero RN at 1.145 is 4.3gr of TiteGroup, in summer temprature this nets a 135-137pf for major matches. In colder weather I back it off a tenth or two.

Is Titegroup inverse temp sensitive?

[RH45]

I've checked my .40 loads with Titegroup, and if there is any temperature sensitivity, I'm not seeing it.

[gm iprod]

I am with Rh on this. I have loaded TG in New Zealand in May (Winter 10deg C) and travelled with that ammo to Columbia MO (Summer 35Deg C) and the velocity is with 20fps of when I left home. If left in the direct sun getting up to some nasty temps until the actual ammo is super heated to 45Deg C+ (like left on an unshaded table at Bianchi Cup for 3 or 4 hours) for a long period of time, there may be some incremental drop off.

WST, 231 / HP38 and a couple of other older style ball powders seem to drop off quite a bit.

[BLSJDS]

Ideally, you want the greatest OAL your gun will shoot reliably with the bullet of choice. Then work up the load. And if you shoot quite a bit, choose from powders that are cheaper and require smaller (weight wise) load per round.

You may have more than one load, practice load/s and match load/s.

Why is that? How does OAL correlate to accuracy? I'm new to reloading (obviously) and have been reading a tremendous amount on this forum, books (A,B,Cs of Reloading, the Speer Reloading Manual), but haven't come across this subject yet.

Thanks!

Dan

[G-ManBart]

Ideally, you want the greatest OAL your gun will shoot reliably with the bullet of choice. Then work up the load. And if you shoot quite a bit, choose from powders that are cheaper and require smaller (weight wise) load per round.

You may have more than one load, practice load/s and match load/s.

Why is that? How does OAL correlate to accuracy? I'm new to reloading (obviously) and have been reading a tremendous amount on this forum, books (A,B,Cs of Reloading, the Speer Reloading Manual), but haven't come across this subject yet.

Thanks!

Dan

The larger the distance between the bullet and the lands, the more opportunity for the bullet to be get out of line with the bore. R,

Edited January 19, 2011 by G-ManBart

[BLSJDS]

The larger the distance between the bullet and the lands, the more opportunity for the bullet to be get out of line with the bore. R,

Thank you!! I just started last week and have been using a load from the Speer manual (115 gr FMJ, 4.2 gr titegroup, 1.135 OAL) for my Beretta 92FS. I'm using the Dillon 550. I did notice some variation in the OAL from my first 25 loads (1.135 dead on) to the last 10 (average of 1.142). Knowing this, I will separate them by length and range test accordingly. Thanks again!

Edited January 19, 2011 by BLSJDS

[gohuskers]

The larger the distance between the bullet and the lands, the more opportunity for the bullet to be get out of line with the bore. R,

Thank you!! I just started last week and have been using a load from the Speer manual (115 gr FMJ, 4.2 gr titegroup, 1.135 OAL) for my Beretta 92FS. I'm using the Dillon 550. I did notice some variation in the OAL from my first 25 loads (1.135 dead on) to the last 10 (average of 1.142). Knowing this, I will separate them by length and range test accordingly. Thanks again!

Part of the OAL variation may simply be mixed brass in addition to stroking the press, reloading bench surface, etc. If you've got a bench that flexes that will add to it, in addition to not being "in rhythm". You'll find that after you reload for a while your loads get more consistent as does your physical movement in stroking the press. Sounds weird but i'm not making it up, I promise!

[BLSJDS]

Part of the OAL variation may simply be mixed brass in addition to stroking the press, reloading bench surface, etc. If you've got a bench that flexes that will add to it, in addition to not being "in rhythm". You'll find that after you reload for a while your loads get more consistent as does your physical movement in stroking the press. Sounds weird but i'm not making it up, I promise!

I definitely believe you; the first 100 I loaded with new brass I got from the range. After that, it was mixed brass that my 10 year old son (now called the Brass Hound ) picked up from the range floor. My bench is rock solid, but I'm definitely not in rhythm yet. Good to know things that can affect OAL .

[G-ManBart]

I definitely believe you; the first 100 I loaded with new brass I got from the range. After that, it was mixed brass that my 10 year old son (now called the Brass Hound ) picked up from the range floor. My bench is rock solid, but I'm definitely not in rhythm yet. Good to know things that can affect OAL .

There are two other common factors in play as well. First, not every bullet is identical, and they usually contact the seating stem somewhere on the curved portion of the bullet (ogive) (rather than the very tip of the nose), so any slight difference will cause a seating depth difference. Second, there will be a slight difference between having a case at all of the stations of the press versus only some...so the first couple, and last couple will usually be different from the rest of that run. R,

[BLSJDS]

There are two other common factors in play as well. First, not every bullet is identical, and they usually contact the seating stem somewhere on the curved portion of the bullet (ogive) (rather than the very tip of the nose), so any slight difference will cause a seating depth difference. Second, there will be a slight difference between having a case at all of the stations of the press versus only some...so the first couple, and last couple will usually be different from the rest of that run. R,

Excellent to know - thank you for taking the time to explain!

I'm looking forward to hitting the range this weekend; good thing it is indoor - it is supposed to be -2 on Saturday - ugh.

[JAFO]

I got out last week to test another load:

Temp: 64 ^oF

Sky: Clear

Distance from muzzle to first screen: ~10'

Gun: Sig P226, 4.4" factory barrel

Powder: 4.4gr Titegroup

Primer: Fed #100 Small Pistol

Bullet: 124gr Zero FMJ (Avg wt of 10 bullets pulled from the same box was 124.7gr. I used this weight for the PF calculation.)

COL: 1.161"

Mixed range brass

String was made up of 63 shots

HI: 1126 / LO: 1031 / AV: 1085 / ES: 95 / Sd: 19.7 / Power Factor: 135 / Group size (from sandbag @ 15 yds): > 6"

The power factor is where I wanted it at 10 over the Minor floor, but the ES and SD are higher than the 4.1gr or 4.3gr loads and the accuracy was awful. That's the reason the string was 63 shots. I thought I was causing the large group size, so I kept shooting until I had gone through five 10-shot groups and one 13-shot group. None of them would stay on a 6" Shoot-N-C target at 15 yds.

After reading some other threads, I've decided to try testing the 4.1gr and 4.3gr at shorter OALs. I'll reshoot the 1.16" loads, then try 1.14" and 1.12". That still has me 0.03" longer than the Sierra load of 1.09" with 4.4gr.

[gm iprod]

JAFO.

We use 125gr JHP Zero and 4.0gr TG at 1.12 maximum. This will go past 125pf but not exceed 130pf. Maybe a little too close for comfort in IPSC.

[JAFO]

Got out yesterday to shoot the two charge weights at varying OALs. Here are the results:

Common conditions

Temp: 58 ^oF

Sky: Clear

Distance from muzzle to first screen: ~10'

Gun: Sig P226, 4.4" factory barrel

Primer: Fed #100 Small Pistol

Bullet: 124gr Zero FMJ (Avg wt of 10 bullets pulled from the same box was 124.7gr. I used this weight for the PF calculation.)

Mixed range brass

All strings were 20 shots

OALs are measured averages of 10 rounds per load

Load 1

Powder: 4.1gr Titegroup

COL: 1.162"

HI: 1055 / LO: 1021 / AV: 1043 / ES: 34 / Sd: 9.4 / Power Factor: 130

Load 2

Powder: 4.1gr Titegroup

COL: 1.139"

HI: 1077 / LO: 1040 / AV: 1053 / ES: 37 / Sd: 9.7 / Power Factor: 131

Load 3

Powder: 4.1gr Titegroup

COL: 1.122"

HI: 1078 / LO: 1039 / AV: 1062 / ES: 39 / Sd: 11.6 / Power Factor: 132

Load 4

Powder: 4.3gr Titegroup

COL: 1.162"

HI: 1092 / LO: 1053 / AV: 1078 / ES: 39 / Sd: 10.8 / Power Factor: 134

Load 5

Powder: 4.3gr Titegroup

COL: 1.140"

HI: 1095 / LO: 1063 / AV: 1080 / ES: 32 / Sd: 8.0 / Power Factor: 134

Load 6

Powder: 4.3gr Titegroup

COL: 1.121"

HI: 1103 / LO: 1073 / AV: 1088 / ES: 30 / Sd: 7.7 / Power Factor: 135

Although the sample sizes aren't huge, there only appears to be about a 10 fps velocity difference per 0.02" OAL change (out of my gun, anyway). I shot these strings as two ten-shot groups off a sandbag at 15 yds through the chrono. Most of the groups were not very good (still 5-6" or greater), but Load #5 gave me two 2" eight-shot groups if I threw out two fliers in each group. I think it's possible that I caused the fliers, so right now that looks like my best load for accuracy and it's giving me the PF I wanted. I'm thinking that my next test should be trying 4.3gr @ 1.13", 1.14", and 1.15" to see if it will tighten up anymore. I'm also contemplating trying some 124gr MG JHPs I have, but with those I'd probably go back to testing @ 1.12", 1.14", and 1.16".

[RH45]

Got out yesterday to shoot the two charge weights at varying OALs. Here are the results:

Common conditions

Temp: 58 ^oF

Sky: Clear

Distance from muzzle to first screen: ~10'

Gun: Sig P226, 4.4" factory barrel

Primer: Fed #100 Small Pistol

Bullet: 124gr Zero FMJ (Avg wt of 10 bullets pulled from the same box was 124.7gr. I used this weight for the PF calculation.)

Mixed range brass

All strings were 20 shots

OALs are measured averages of 10 rounds per load

Load 1

Powder: 4.1gr Titegroup

COL: 1.162"

HI: 1055 / LO: 1021 / AV: 1043 / ES: 34 / Sd: 9.4 / Power Factor: 130

Load 2

Powder: 4.1gr Titegroup

COL: 1.139"

HI: 1077 / LO: 1040 / AV: 1053 / ES: 37 / Sd: 9.7 / Power Factor: 131

Load 3

Powder: 4.1gr Titegroup

COL: 1.122"

HI: 1078 / LO: 1039 / AV: 1062 / ES: 39 / Sd: 11.6 / Power Factor: 132

Load 4

Powder: 4.3gr Titegroup

COL: 1.162"

HI: 1092 / LO: 1053 / AV: 1078 / ES: 39 / Sd: 10.8 / Power Factor: 134

Load 5

Powder: 4.3gr Titegroup

COL: 1.140"

HI: 1095 / LO: 1063 / AV: 1080 / ES: 32 / Sd: 8.0 / Power Factor: 134

Load 6

Powder: 4.3gr Titegroup

COL: 1.121"

HI: 1103 / LO: 1073 / AV: 1088 / ES: 30 / Sd: 7.7 / Power Factor: 135

Although the sample sizes aren't huge, there only appears to be about a 10 fps velocity difference per 0.02" OAL change (out of my gun, anyway). I shot these strings as two ten-shot groups off a sandbag at 15 yds through the chrono. Most of the groups were not very good (still 5-6" or greater), but Load #5 gave me two 2" eight-shot groups if I threw out two fliers in each group. I think it's possible that I caused the fliers, so right now that looks like my best load for accuracy and it's giving me the PF I wanted. I'm thinking that my next test should be trying 4.3gr @ 1.13", 1.14", and 1.15" to see if it will tighten up anymore. I'm also contemplating trying some 124gr MG JHPs I have, but with those I'd probably go back to testing @ 1.12", 1.14", and 1.16".

Even though I prefer the recoil impulse of a 125 grain bullet over that of a 115, if you're looking for accuracy, you can find some, try some Zero, 115 grain jhps, in once-fired brass from your pistol. When I was running a SIG 226, my groups averaged around an inch at 25 yards with this combination.