Handi Rifle Only HOT Supersonic Loads

[Ramuel]

I am coloring WAAAAAYYY outside the lines here people! This is going to be long winded and I'll be rambling like a retard but stick with me!

Recently I loaded up some 125grain SST bullets in 300BLK
-W296 Powder I worked up to 17.5 grains(Hornady's Max)
-Virgin Starline Brass
-Federal AR Match Primers
-C.O.L. of 2.100"
Average Velocity out of my Handi Rifle(16.25" Barrel) was 2211fps measured by a Lab Radar Chronograph. Not bad. Although I was not using a optic conducive to precision shooting, the accuracy was not up to par.
In a quest for more accuracy, I got out the O.A.L Gauge. The distance to the lands in my rifle with this bullet is C.O.L. of 2.254". That's a lot of jump to the lands when seated to 2.100". This got me thinking... Seat the bullets out close to the lands, increase case capacity, and fill it with flammable stuff. What could go wrong?

For the next load I chose 2.234" C.O.L. which gives me only .174" of insertion into the brass. Yea its sketchy but it's a single shot rifle. I dont need to worry about seating depth and neck tension all that much. I shot them yesterday and here is the velocity results. All using W296. Same primers, bullet, and brass. The only signs of pressure was a slow linear flattening of the primers. At 18.5 the primers still have rounded edges. Nothing to worry about.
-17.5 = 2137fps
-17.7 = 2184fps
-17.9 = 2219fps
-18.1 = 2216fps
-18.3 = 2256fps
-18.5 = 2262fps

My next test will start at 18.5, working up .1 grain at a time to 19.1 grains. I already loaded these charge weights and even at 19.1 there is still room left in the case. No where near compressed. I used CCI 41 primers for these loads hoping that the harder cup will withstand the increased pressure. I plan on shooting these as soon as Friday and will post velocity and group results.

I would be a pig in shit if I could hit 2350fps or more with a 125grain bullet. I am going to keep testing with different powders and bullet combinations so if you guys have anything you would like me to try, or have recommendations, let it be known.

[dellet]

I am coloring WAAAAAYYY outside the lines here people! This is going to be long winded and I'll be rambling like a retard but stick with me!

Recently I loaded up some 125grain SST bullets in 300BLK
-W296 Powder I worked up to 17.5 grains(Hornady's Max)
-Virgin Starline Brass
-Federal AR Match Primers
-C.O.L. of 2.100"
Average Velocity out of my Handi Rifle(16.25" Barrel) was 2211fps measured by a Lab Radar Chronograph. Not bad. Although I was not using a optic conducive to precision shooting, the accuracy was not up to par.
In a quest for more accuracy, I got out the O.A.L Gauge. The distance to the lands in my rifle with this bullet is C.O.L. of 2.254". That's a lot of jump to the lands when seated to 2.100". This got me thinking... Seat the bullets out close to the lands, increase case capacity, and fill it with flammable stuff. What could go wrong?

For the next load I chose 2.234" C.O.L. which gives me only .174" of insertion into the brass. Yea its sketchy but it's a single shot rifle. I dont need to worry about seating depth and neck tension all that much. I shot them yesterday and here is the velocity results. All using W296. Same primers, bullet, and brass. The only signs of pressure was a slow linear flattening of the primers. At 18.5 the primers still have rounded edges. Nothing to worry about.
-17.5 = 2137fps
-17.7 = 2184fps
-17.9 = 2219fps
-18.1 = 2216fps
-18.3 = 2256fps
-18.5 = 2262fps

My next test will start at 18.5, working up .1 grain at a time to 19.1 grains. I already loaded these charge weights and even at 19.1 there is still room left in the case. No where near compressed. I used CCI 41 primers for these loads hoping that the harder cup will withstand the increased pressure. I plan on shooting these as soon as Friday and will post velocity and group results.

I would be a pig in shit if I could hit 2350fps or more with a 125grain bullet. I am going to keep testing with different powders and bullet combinations so if you guys have anything you would like me to try, or have recommendations, let it be known.

[Ramuel]

Yikes. Is that the path you think I'm headed down? I'm taking the loads seriously. I've never ventured this far out of published load data before. The the load of 18.5 with the longer overall length showed less pressure than the 17.5 at 2.100" so I'm hoping I can at least shoot up to 18.8 grains(The max for h110 in hornady manual).

[dellet]

Yikes. Is that the path you think I'm headed down? I'm taking the loads seriously. I've never ventured this far out of published load data before. The the load of 18.5 with the longer overall length showed less pressure than the 17.5 at 2.100" so I'm hoping I can at least shoot up to 18.8 grains(The max for h110 in hornady manual).

If you keep chasing speed sooner or later something happens.

The only thing you said that is questionable is switching primers and that's for a couple of reasons.One is safety, the other is practical.

On the practical side, there is a good chance that they just won't work. The Handi might not have the hammer speed to pop the primer.

On the safety side, trying to mask a pressure sign is never a good idea.

For load development you need to look at more sources. Using a single source can get you in trouble and you miss trends in different powders.

Not to pick on the new guy, but you think you're coloring outside the lines, when in reality you haven't even moved up to colored crayons yet.
https://sierrabulletsblog.com/2017/12/2 ... load-data/


Note the difference between H110 and 296. same powder different lots.

You're working the load up in a safe way, but towards the top end, it will go from bang to boom in a small window. 23-2350 is no problem with the combination you have, but the farther out you seat the bullet, the harder consistent accuracy will become. Go slow and if it gets hard to open the action or eject the case, stop, no matter what the primer looks like.

[Ramuel]

Thanks for the replies and advice. I'm knew to this forum but I've been hand loading for about 3 years now mainly .223, .270, and 6mm Creedmoore. I still have a lot to learn for sure but I feel pretty comfortable.
I dont just use Hornady for data. I have Sierras manual and use hodgdon's website a lot too. Ive never used Hornady 300blackout brass but the starline brass must have less capacity than the Hornady. Hornady, Sierra, and Hodgdon from what I can tell all use the Hornady brass for 300 blackout. I can't imagine putting 20.0 grains in the Starline brass that I have. It would be way up in the neck and be really compressed. Maybe I'm just a wussy but I'm not going to go that high.
Anyhow I cant wait to try these out. 300 blackout so far has been really fun to load for with subsonics. I really would like to see what the limits are with supers in the handi (without blowing my gun up) in the 300 blackout. I'll keep you posted with the results after the next range trip.

[dellet]

Thanks for the replies and advice. I'm knew to this forum but I've been hand loading for about 3 years now mainly .223, .270, and 6mm Creedmoore. I still have a lot to learn for sure but I feel pretty comfortable.
I dont just use Hornady for data. I have Sierras manual and use hodgdon's website a lot too. Ive never used Hornady 300blackout brass but the starline brass must have less capacity than the Hornady. Hornady, Sierra, and Hodgdon from what I can tell all use the Hornady brass for 300 blackout. I can't imagine putting 20.0 grains in the Starline brass that I have. It would be way up in the neck and be really compressed. Maybe I'm just a wussy but I'm not going to go that high.
Anyhow I cant wait to try these out. 300 blackout so far has been really fun to load for with subsonics. I really would like to see what the limits are with supers in the handi (without blowing my gun up) in the 300 blackout. I'll keep you posted with the results after the next range trip.

The case capacity of new brass is always low. Now that you have some fired compare them. It might be worth checking the capacity just so you know how different it might be. If they are close to spec a fired case will hold just over 24 grains of water weight. 296 through a drop tube will be real close to water weight around 24-24.5 grains depending on trim length. Not uncommon to pick up a full grain of capacity after firing.

A lot of factory ammo with 125 grain bullets have a listed velocity 22-2250 fps.

Always good to see someone work up and document, it really helps others.

[rebel]

I too admire someone willing to test the limits. That understanding comes with reading through the archives of this forum, learning how fast pistol powder reacts to increased capacity, compression, new versus fire formed brass. The other cartridges you mentioned having experience with have their limits, but are much more forgiving with the powders used. I think you have an understanding of what it takes to put together a good round, but you are on the edge and won't hit another node with more powder. Pick your best load thus far, and stick with it.

[Ramuel]

So I tested ONE of the fired brass vs the ONE of the virgin brass for water weight. The virgin held 22.0 grains of water and the fired held 22.31 grains of water. I measured the virgin / fired brass on my head space comparator and for overall length. I measured about 25% of the brass and found that on average they did not stretch at all in terms of length or head space dimensions.

I forgot to mention that the loads I plan to shoot next are not virgin brass but on their second firing. I used a full length Lee sizing die but I did not bump the shoulder at all. I adjusted the die until the entirety of the neck was resized. This is the same setting I used to uniform the factory brass before loading them the first time.

[dellet]

What were the base to datum measurements before and after firing?

[Ramuel]

Datum line measurements
Virgin = ~1.075"
Fired = ~1.076"
That's with Hornady's B-.350" bushing