150 Grain Subsonic Load?

[thecameraman79]

This is my first post on the forum but have browsed quite a bit so be gentle. I have been reloading for a 9" SBR with the 762-SDN-6 with much success. I just bought my wife a handi-rifle and a 9mm can because my SBR is just too heavy for her with a fully loaded magazine and the can hanging on the front.

I have 220SMK and 150 gr Sierra bullets in my possesion and I know one of the great things about the handi-rifle and bolt actions is that you can use a MUCH wider range of bullets at subsonic speeds since you don't have to worry about the action cycling. I'm really interested in using up the 150 grain bullets but don't know where to start. I have H110 and A1680 and no chronograph (I know I know, it's on my wish list!). I've looked but haven't been able to find any loads with these combinations. The loads have to stay subsonic with the pistol can. Please if anyone can give me an idea of a starting point for the handi rifle with the original 16" barrel I'd appreciate it.

Thanks,
Fred~

[NoHarmNoFAL]

Welcome!

I too have the handy rifle and have played with subsonic lighter loads.

I am sorry but I don't have a specific recipe for A1680 and 150's but I can give you an idea where to start.

You can extrapolate some values though. If the starting load for a 150gr bullet and A1680 is 19.4gr @ 1895fps and max load is 21.7gr @ 2057fps you can get an average grains of powder per foot per second value of 96.23fps/gr. So if you want to be subsonic it looks like roughly 10gr should get you close.

Now with all that said you certainly should start with a published load and work down to your desired result. This extrapolation has some variance in it that can't be accounted for like burn efficiency rates at sub optimum pressures and such so only use it is a suggestion and not gospel.

I have used this method to get subsonic rounds with unpublished recipes with success but I did have to work down to the load and carefully looked for the danger signs.

Good luck!

[thecameraman79]

Welcome!

I too have the handy rifle and have played with subsonic lighter loads.

I am sorry but I don't have a specific recipe for A1680 and 150's but I can give you an idea where to start.

You can extrapolate some values though. If the starting load for a 150gr bullet and A1680 is 19.4gr @ 1895fps and max load is 21.7gr @ 2057fps you can get an average grains of powder per foot per second value of 96.23fps/gr. So if you want to be subsonic it looks like roughly 10gr should get you close.

Now with all that said you certainly should start with a published load and work down to your desired result. This extrapolation has some variance in it that can't be accounted for like burn efficiency rates at sub optimum pressures and such so only use it is a suggestion and not gospel.

I have used this method to get subsonic rounds with unpublished recipes with success but I did have to work down to the load and carefully looked for the danger signs.

Good luck!

NoHarmNoFal,

Thanks for the reply! What powder/load to you use for your handi rifle and 150 gr loads? I'm willing to buy powder since it doesn't apear anyone is using my two powders for a subsonic 150 gr load. I have only been reloading for about a year but know to look for bulging cases and blown primers for overpreasure signs but what are underpreasure/danger signs to look for?

Thanks!

[NoHarmNoFAL]

I started with Lil'Gun and A1680 but for light bullets I only use Lil'Gun.

I am saving my 1680 for my AR loads and using Lil'Gun for AR supers and Handirifle pet loads.

[AR-300]

just don't extrapolate H110 loads!!!

For those loads listed where a starting load is not shown, start 10% below the suggested maximum load and then approach maximums carefully, watching for any sign of pressure (difficult extraction, cratered and flattened or blown primers, and unusual recoil). H110 and Winchester 296 loads should not be reduced more than 3%.

Reduce H110 and Winchester 296 loads 3% and work up from there. H110 and Winchester 296 if reduced too much will cause inconsistent ignition. In some cases it will lodge a bullet in the barrel, causing a hazardous situation (Barrel Obstruction). This may cause severe personal injury or death to users or bystanders. DO NOT REDUCE H110 LOADS BY MORE THAN 3%.

http://data.hodgdon.com/main_menu.asp

[sranch]

I make 147 grain FMJ subsonic rounds all the time. AND they cycle in my AR.
BUT

as bullet weight decreases so does reliable speed. So heavier bullets will yield more consistent fps than lighter ones. With the loads I make using 9 grains of A1680 i get speeds from 850 fps to 1250. so staying under the sound barrier is very unreliable. I have been wondering if there's a product like a "filler" that can be mixed with the powder to yield more consistent burns AND case fill. I think this would solve most of my problems.

Also, I have a pistol length gas system. Although I could get 155 grain bullets to reliably cycle with 10 grains of A160 in my carbine length system (16 inch barrel). But of course inconsistent speeds.

[thecameraman79]

I make 147 grain FMJ subsonic rounds all the time. AND they cycle in my AR.
BUT

as bullet weight decreases so does reliable speed. So heavier bullets will yield more consistent fps than lighter ones. With the loads I make using 9 grains of A1680 i get speeds from 850 fps to 1250. so staying under the sound barrier is very unreliable. I have been wondering if there's a product like a "filler" that can be mixed with the powder to yield more consistent burns AND case fill. I think this would solve most of my problems.

Also, I have a pistol length gas system. Although I could get 155 grain bullets to reliably cycle with 10 grains of A160 in my carbine length system (16 inch barrel). But of course inconsistent speeds.

That is an EXTREME spread in velocity. I'm sure there has to be better loads for 150 grain bullets in a handi/bolt action. I'm willing to buy a different powder since it doesn't look like the H110 or A1680 are a good powder for subsonic loads of the lighter (150 grain) bullets.

[tallburnedmidget]

This is my first post on the forum but have browsed quite a bit so be gentle. I have been reloading for a 9" SBR with the 762-SDN-6 with much success. I just bought my wife a handi-rifle and a 9mm can because my SBR is just too heavy for her with a fully loaded magazine and the can hanging on the front.

I have 220SMK and 150 gr Sierra bullets in my possesion and I know one of the great things about the handi-rifle and bolt actions is that you can use a MUCH wider range of bullets at subsonic speeds since you don't have to worry about the action cycling. I'm really interested in using up the 150 grain bullets but don't know where to start. I have H110 and A1680 and no chronograph (I know I know, it's on my wish list!). I've looked but haven't been able to find any loads with these combinations. The loads have to stay subsonic with the pistol can. Please if anyone can give me an idea of a starting point for the handi rifle with the original 16" barrel I'd appreciate it.

Thanks,
Fred~

Check here http://300blktalk.com/forum/viewtopic.php?f=141&t=81579. Be sure to keep this link handy as the link to this page is broken in Sticky thread on the handloading PET Subsonic A1680 150-200gr loads. You must Google "300blktalk Subsonic A1680 150" to find the page.

Anyhow, look at the last post and you will find my work with the 150gr Barnes MPG bullet. The Barnes MPG is probably longer than a 150 SMK but this should get you in the ball park and you will need to adjust COAL and/or powder from there. W/out a chrony you are flying blind. Be sure to:
1. Don't shoot any loads with a suppressor on unless they are stabalizing on the target (crips round holes, not elongated or square corner holes)]
2. Work down in small increments (.2gr or so) until you no longer hear the supersonic crack, once again w/out a suppressor
3. Finally load up about 10-15 of each load you believe to be in your sweet spot of good subsonic loads (3 different loads should be good), fire the loads through the suppressor and note any going supersonic or showing stability issues (they should all still be stable if you followed step 1)
4. Pick the most accurate load that did not go supersonic with the suppressor on

This should do the trick for you. Note that what I mention is a quiet a bit of loading work and shooting to find a subsonic load for 1 particular bullet and would need to be done again for a different bullet and/or weight. A chrony would easily cut the work in half or less

Good luck, and remember to be safe

[thecameraman79]

This is my first post on the forum but have browsed quite a bit so be gentle. I have been reloading for a 9" SBR with the 762-SDN-6 with much success. I just bought my wife a handi-rifle and a 9mm can because my SBR is just too heavy for her with a fully loaded magazine and the can hanging on the front.

I have 220SMK and 150 gr Sierra bullets in my possesion and I know one of the great things about the handi-rifle and bolt actions is that you can use a MUCH wider range of bullets at subsonic speeds since you don't have to worry about the action cycling. I'm really interested in using up the 150 grain bullets but don't know where to start. I have H110 and A1680 and no chronograph (I know I know, it's on my wish list!). I've looked but haven't been able to find any loads with these combinations. The loads have to stay subsonic with the pistol can. Please if anyone can give me an idea of a starting point for the handi rifle with the original 16" barrel I'd appreciate it.

Thanks,
Fred~

Check here http://300blktalk.com/forum/viewtopic.php?f=141&t=81579. Be sure to keep this link handy as the link to this page is broken in Sticky thread on the handloading PET Subsonic A1680 150-200gr loads. You must Google "300blktalk Subsonic A1680 150" to find the page.

Anyhow, look at the last post and you will find my work with the 150gr Barnes MPG bullet. The Barnes MPG is probably longer than a 150 SMK but this should get you in the ball park and you will need to adjust COAL and/or powder from there. W/out a chrony you are flying blind. Be sure to:
1. Don't shoot any loads with a suppressor on unless they are stabalizing on the target (crips round holes, not elongated or square corner holes)]
2. Work down in small increments (.2gr or so) until you no longer hear the supersonic crack, once again w/out a suppressor
3. Finally load up about 10-15 of each load you believe to be in your sweet spot of good subsonic loads (3 different loads should be good), fire the loads through the suppressor and note any going supersonic or showing stability issues (they should all still be stable if you followed step 1)
4. Pick the most accurate load that did not go supersonic with the suppressor on

This should do the trick for you. Note that what I mention is a quiet a bit of loading work and shooting to find a subsonic load for 1 particular bullet and would need to be done again for a different bullet and/or weight. A chrony would easily cut the work in half or less

Good luck, and remember to be safe

Thanks! Thats a good start of what I'm looking for! I'm kinda surprised though. I use 11.2 gr of A1680 for my 9" AR and they stay subsonic. Just from the little I know I would think a 70 gr lighter bullet with 11.1 gr of A1680 with 7" more of barrel to travel through would pick up even more velocity and would go supersonic. Thats just from the thinking in my head I understand not real numbers. I know I know I am going to have to ask santa for a chronograph for christmas I guess. I've wanted one but I've been spoiled by the load data for the 220 gr SMK's that I haven't had to chronograph them to worry if they would go subsonic or not. Thanks for the load data!

[rebel]

If you don't care if they cycle the AR, and really want a quiet load, two words-Trail Boss. I haven't attempted this with 220's because I don't think you can get enough powder in the case to push it out. A 150 however would be no prob! They are a blast in my Handi or using the AR as a single shot.