Should I keep pushing? [Archive] - Glock Talk

PDA

View Full Version : Should I keep pushing?


Andrew Wiggin
09-08-2012, 21:32
I worked up a 10mm load of 180gr XTP over AA7. At the max charge listed in the Hornady manual, 12.0 gr, I have no pressure signs at all and pretty consistent velocities. Do you think it would be safe to continue working up in 0.2 gr increments? Firearm is 4.5" barreled Witness.


Chrono results for 12.0gr load:

1259
1270
1282
1271
1266
1284


11.8:

1231
1260
1252
1254
1255
1245


11.6:

1232
1213
1212
1226
1241


11.4:

1190
1205
1228
1222
1212


11.2:

1203
1198
1134
1197


11.0:

1162
1223
1265
1195

_The_Shadow
09-08-2012, 21:57
Looks like some nice uniform numbers, how was he accuracy with the 12.0 grain loads? Speed and accuracy in combination would be where you want to be... :)

Andrew Wiggin
09-08-2012, 22:27
I wasn't shooting on paper. Just through the chrono. Theoretically a really consistent load should be very accurate, too.

countrygun
09-08-2012, 22:35
I wasn't shooting on paper. Just through the chrono. Theoretically a really consistent load should be very accurate, too.


ERROR

Consistency is nice, but it isn't a sign of an accurate load by itself. I can get very consistent velocity results with a load that groups like a handful of rocks.

i would say that about 80% of the time, from .38 special to .44 mag, my best loads, accuracy wise have been around 10% or so below the manuals maximum load.

gofastman
09-09-2012, 02:36
why not just move to AA#9?

Andrew Wiggin
09-09-2012, 11:18
I said "theoretically." ;^)

I'll check it on paper later but I just wanted to get them all across the chrono. It was getting late.

gwsanfor
09-09-2012, 19:43
Andrew,

What's your COL, and have you measured the actual bullet length, maybe even the Maximum Case Capacity? I have a little time available this week, and could give you an estimate of pressure and velocity above 12.0 gr, if you have that data.

You may, as others suggested, want to move to AA#9 and consider accuracy as well as velocity. If you are just looking for velocity and nothing else, there are several better-suited powders.

Andrew Wiggin
09-10-2012, 09:36
I don't really need anything faster. I just wondered if it would be safe to continue. Other loads I worked up started showing pressure signs below the max. When I posted this thread on another forum a user mentioned that the first pressure sign he saw with a load was a case failure.

It would probably be best to stay inside published data.

Taterhead
09-10-2012, 19:06
No reason to keep pushing. Not worth it for a few more fps. That is already a pretty stout load and well above Accurate's max. Most groups with 10mm are going to be somewhere less than max loads anyway.

I personally do not find much value in doing load workups without getting them on paper. Before I would even think about pushing further, I would get the loads on paper to see what really works. If wanting faster velocities, no. 9 will be more forgiving.

Stay safe.

glockout
09-10-2012, 21:21
Your standard deviation is best at 12.0 with 9.5, 11.8 is 10.2, 11.6 is 12.3, 11.4 is 15, 11.2 is 32 and 11.0 is 43. Thanks for sharing your data.

Andrew Wiggin
09-11-2012, 11:47
Andrew,

What's your COL, and have you measured the actual bullet length, maybe even the Maximum Case Capacity? I have a little time available this week, and could give you an estimate of pressure and velocity above 12.0 gr, if you have that data.

You may, as others suggested, want to move to AA#9 and consider accuracy as well as velocity. If you are just looking for velocity and nothing else, there are several better-suited powders.

Sorry, missed your question earlier. COL is 2.255". Bullet length is 0.618" and Hornady lists BC as 0.164.