OAL Relation to Velocity

[brisix]

Today I went to the range to test some new loads and the results surprised me.   I decided to take my tried and true load (Berry's 124 HBRN, 4.0Gr titegroup, OAL 1.132) and increase the OAL to 1.160.  I am doing this to get better reliability in my Scorpion from extended mags. 

If I average out the 8 chrono sessions with my old load I came to 1074 fps.  That's pretty close to what I would see at chrono at a major USPSA match.

My expectation was that I would need to increase my charge by .1gr to maintain the same velocity with the longer OAL.

Results - Average from 5 shots at 3 yrds through a SP-01 Tactical 
4.0gr - 1082
4.1gr - 1116
4.2gr - 1120
4.3gr - 1145

I did not expect the new load with the longer OAL to get close to the same velocity with the same charge.   

Next step is testing the load after mass production on the 1050.

[Wobbly]

In your shoes, first I'd check your accuracy because it probably went out the window.

[brisix]

Accuracy was similar to before.   I am not the best bulleye shooter from a rest.  Its possible a person with a better trigger find could see a difference. 

For me I shoot high volume for competition.  My key concern is reliability and not blowing up my gun.  If the round goes bang and I can hit the A zone at speed twice at 25 yrds I am good.

One thought I had on why I am not seeing a change in velocity is that titegroup is a fast burning powder and is not as sensitive, in terms of velocity, to OAL for a given charge, within the green zone. 

[Wobbly]

One thought I had on why I am not seeing a change in velocity is that titegroup is a fast burning powder and is not as sensitive, in terms of velocity, to OAL for a given charge, within the green zone.

My exact thought also.

[1SOW]

Your just going super sonic with your max. load
  If the BRY bullet is still stable,  looks like you're in good shape for a match at the distances you mentioned.  Our local match is the same,  Max 25 yards.