Lightweight Lehigh's at ludicrous speeds!!!

[Hvymax]

I've been truly amazed at how fast these go without stupid pressures. 68gr 357 Sig do 2,300 fps out of a 7" barrel and 2,100fps out of my Bond Arms. 98gr go 3,200fps out of my 350 Legend. Next I've decided that I'm going to see what 125gr will do out of my Dan Wesson 44. My loose calculations estimate about 2,800-3,000 fps. You never really know what different powders will do with different weight and material bullets until you start throwing loads. I hope I don't need to many barrels to dial it in.

 

[NC FNS]

Does it change POA much compared to standard weight bullets?

 

[Hvymax]

Does it change POA much compared to standard weight bullets?

Yes it can. In my Bond Arms within it's normal applications it's fine. I'm planning on ordering a few barrels for the Dan Wesson once I get a few baselines from the barrels I have laying around. Maybe I'll get lucky. Twist Rate, Barrel Length and Rifling cut are the key factors. It's great that the AR brought this front and center for people to see. Before the 1:9/1:7 twist arguments hardly anyone thought about rifling other than it was just there.

 

[Hvymax]

Does it change POA much compared to standard weight bullets?

My original research in the 80's started when I started pushing 300+gr bullets beyond normal speeds. The standard barrels wouldn't stabilize them. The same thing happened when I shot 1,000gr 700NE bullets out of standard 1:36" 12ga slug barrels. Mo twist Mo better.
Where the science gets interesting then. Lighter bullets slower twist right? What if they are going twice as fast??? Will the rifling effectively engage the bullet? Should I try gain twist to reduce stress on the bullet? Will the gain twist shear the bullet surface as it transitions? Something else to work into my schedule and budget!!!

 

[the_leper_colony]

...Where the science gets interesting then. Lighter bullets slower twist right? What if they are going twice as fast??? Will the rifling effectively engage the bullet? Should I try gain twist to reduce stress on the bullet? Will the gain twist shear the bullet surface as it transitions? Something else to work into my schedule and budget!!!

I remember reading an interesting article 30-40 years ago, where the author was pushing some short & light bullets to high velocities out of one of the big-bore magnum cases (.458 Win?). Obviously the aerodynamics sucked, but the energy levels & terminal effects at short range were "through the roof"! Way beyond my personal capabilities, but I appreciate the potential entertainment value. (Reminds me of the time many years ago, when I tried out a .30-06 110gr varmint load on an expired XXXL can of tomato paste - who needs tannerite?) Fun comes in many forms!

As always IMHO, FWIW, YMMV, etc., etc.

 

[Hvymax]

 

[Feel the 'Pane]

I've gone with the 'light and fast' load for personal defense for yrs.

82gr Barnes solid copper hp in my 357 Sig over 11.3gr of Power pistol. Not quite compressed and chrono's 1720fps out of 3.5" barrel.

My question is: how are you measuring your pressures? Flattened primers or split cases? I loved seeing your 2,100fps video, and was considering maybe going a little hotter with my SD load, but I don't want to destroy my 229, sneaking up on an already max load.

 

[Hvymax]

I've gone with the 'light and fast' load for personal defense for yrs.

82gr Barnes solid copper hp in my 357 Sig over 11.3gr of Power pistol. Not quite compressed and chrono's 1720fps out of 3.5" barrel.

My question is: how are you measuring your pressures? Flattened primers or split cases? I loved seeing your 2,100fps video, and was considering maybe going a little hotter with my SD load, but I don't want to destroy my 229, sneaking up on an already max load.

I watch the primers and cases for the most part. I generally stick to available data not exceeding. I did throw caution slightly to the wind with the Bond Arms. The volume of powder was within the norm for the case and not compressed. 1,700fps is about what I get with #9 from that gun. Faster in longer barrels. V3N37 is my go to for compact pistols and was into the 1,900's. CFE broke 2,000 and Universal ftw 2,100fps.
What I learned was V3N37 is best with heavier 125-147gr bullets, CFE a little more neutral and Universal best with light bullets. I just set the measure for volume and did weigh. The brass was a little worse for wear with the Universal. Again I knew that there wasn't anything that I could fit in the case that would damage the gun being used. The same volume of #9 is midway between normal and+P which is usually where I shoot for. The way I like to maximize performance is matching powder to barrel length. I can frequently get higher velocities at lower pressures which is the best of both worlds. I remember communicating with Ed Hubel back in the 80's - 90's about the 12ga from Hell. Mad Science at it's finest. He used slow rifle powders like Retumbo and 50bmg behind shotgun slugs. Higher velocities with lower chamber pressures.