450 Heavy For Caliber and Subsonic
Posted: Sat Mar 30, 2019 5:13 am
Have a couple years pouring over this site and want to thank everyone for their contributions.
About the same time I was working up this post in Word I saw the post by Rklenke, good post bud, going to pick up some of that Shooter’s World Blackout if I can find any.
I do a lot of night hog hunting throughout the year and would like to have a heavy and viable round that is subsonic. I figured if the .458 SOCOM could do it, so can we.
I do not want to pay for some designer bullets aka Black Butterfly.
http://www.450bushmaster.com/viewtopic.php?f=5&t=16120&sid=6db26b5d703dfc8474e066907443896d
I love large calibers and the heavy bullets that go along with them.
When I look around different forums I see a smattering of people searching for heavy bullet data for the .450 Bushmaster but it is a hunt and peck search still for this “young” caliber.
USE AT YOUR OWN RISK, this goes without saying and I appreciate any challenges to data in this experimental area:
I do not want to change springs unless it comes down to a requirement. (as of 3/22 I am still waiting on my suppressor but will go back and edit results as such, guessing July before I get it, .45 HYBRID).
Firearm: 16”, 1-24 Twist, Home Built, .451 slugged.
May be adding a 1:16 AR-556 18” Ruger for my daughter. But using the above for testing because I figure if a 1-24, 16” stabilizes the bullet, then the 1-16 will do so as well. Mid-length Gas system.
According to velocity calculators the 1-24 will have a gyroscopic stability (SG) of 1.47 at 1,080fps when firing our upper end of bullet weights…525 may be a push. This is at the upper end of marginal stability as an SG of 1.5 is recommended, so we will need also indicate in the loads if the bullet keyholed. A 1-16 barrel will give an SG of 3.32 with the same data as above, So the 510 Hunter Supply will act as my focus. This is a readily available cast bullet as I do not cast or powder coat my own.
I have .454, .452 and .451 swagers. Jacketed bullets are brought down in three steps, Cast in two.
Due to readily available, I purchased the following projectiles.
1. “350 OT” - 350Gr Oregon Laser Trail - .452 - .921 Long after sizing (LAS)
2. “400 Speer” - .4515 - .987 LAS
3. “405 OT” - 405Gr Oregon Laser Trail - .452 – 1.025 LAS
4. “405 BT” - 405g WFNGC Beartooth – On Order (reading varying opions on firing through a Supressor, seems like a potentially bad idea to me).
5. “510 HS” - 510Gr RNPB Hunter’s Supply - .452 - 1.34 LAS, These actually weigh about 512gr on average. Do not seat these past a COL of 2.236 (in my rifle), as the bullet will hit the lands.
6. “525 BT” - 525g WFNGC Beartooth Piledriver - On Order
Powders Avaialble:
IMR4198, IMR4227, Trailboss, AA 2015, AA 2495, VVN120C, VVN32C (Tinstar), Lil’Gun, MP300, 296, BLC-2, H380, H414, RL7, lots of others and shotgun powders (Wife says the basement looks like a Cabelas).
Have lots of other powders if you think there are other viable alternatives for good fill and burn percentages. Obviously we have very different powders to push a 200gr vs a 525gr!
As a side note, I find it amazing that this cartridge can push a 180gr projectile up to a 525gr projectile (albeit has its sweet spot). Again, I stress to anyone, that this is a highly experimental area and to validate and use any of this data at your own risk. Like anything on the internet, VERIFY!
In the loads below I did not have any noticeable case head growth, so I did not record it.
Even in the 400gr supersonic load below I had no discernable case head growth deviation from normal, probably because I am only aiming for the 40kpsi line or below.
For all loads below:
Brass: Starline Brass used in all loadings @ 1.69” case Length
Primer: Rem 7 ½ used in all loadings unless noted
Crimp: .4755 Taper and Stab Crimp Placed in an available Cannelure.
For the QL data, I resized the 400g Speer for most and checked by resizing the 500gr .458 down to .452 (Cast) or .4515 (Jacketed). Brass held 61g of water, So a lot of loads came in under what QL predicted from a default of 60g of water.
Load 1 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 350g OT
Powder: 13.5g - Trailboss
OAL: 2.13
QL Predicted Pressure, FPS, %Fill, %Burn – 27,849 psi, 1,076 fps, 96.3%F, 100%B
Chronograph Readings: 1080, 1060, 1073 SD: 10.1
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, Very Clean, very very quiet and light recoil. Would be GREAT in a bolt gun for a kid or if you don’t mind manually cycling an AR.
Load 2 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 350g OT
Powder: 14g Tin Star
OAL: 2.13
QL Predicted Pressure, FPS, %Fill, %Burn – 31600 psi, 1,082 fps, 74%F, 100%B (Under 80% Fill)
Chronograph Readings: 1124, 1130 SD: 4.2 (Only picked up two on chrony)
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, very very quiet and light recoil. Clean Load, would be GREAT in a bolt gun or for a kid, trailboss above was cleaner in Load 1.
Trailboss is right in the wheelhouse for a 350g bullet at subsonic.
Load 3 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 400g Speer
Powder: 15.5g Tin Star
OAL: 2.17
QL Predicted Pressure, FPS, %Fill, %Burn – 39,650 psi, 1,078 fps, 84%F, 100%B
Chronograph Readings: 1061, 1083, 1068 SD: 11.2
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, very quiet and light recoil.
Very Clean Load, would be GREAT in a bolt gun or for a kid.
TrailBoss was tested under a 400g Speer, but only reached 880, 860, 870…did not cycle.
Conclusion…this would be my go-to in a bolt gun for subsonic with Tin Star and 400g.
Maybe a suppressor will add enough back-pressure to cycle.
Load 4 – Fired (Not Attempting Sub-sonic), no sup., just looked like a good combo to zing a 400gr bullet.
Bullet: 400g Speer
Powder: 35g AA 1680
OAL: 2.17
QL Predicted Pressure, FPS, %Fill, %Burn – 39,633 psi, 1,584 fps, 88.7%F, 92%B
Chronograph Readings: 1490, 1460, 1477 SD: 15
Ambient Temp: 40F
Group Size: 1” Group…Very Clean, good well balanced load. Darn good Heavy Load, Bullet Stabilized. Replicates ~4570 light loading in recoil.
This may be a new go to load to add to my 275gr barnes and 200gr barnes!
Cycle Action: Yes, With Authority. Lots of room to go with this in a bolt gun I believe.
Case head growth - NO.
For the loads below…FOCUS Projectile.
Bullet: 510gr HS. 1.34” Long,
Case: 1.69”
All below OAL: 2.235”
QL Predicted Pressure, FPS, %Fill, %Burn: Options Below
Removed SD as I only loaded 2 rounds per loading due to expense and first round pass to see if action would cycle or bullet would stabilize.
Important Note on Crimping: As you can see the 510grn projectile is seated deeper then where it is at .452" so you MUST adjust your taper crimp to just bring the case mouth down to .475 with very little pressure from the press. Then you have to use a stab crimp in an appropriate groove. I chose the middle groove, no particular reason its just where it fell on my blocked up Legendre Crimp setup with a spacer.
510 Grain Hunter's Supply seems to be the ticket, but what a beautiful monstrosity! (Beauty is in the the eye of the beholder).
Load 5 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 22g IMR 4198
QL Predicted Pressure, FPS, %Fill, %Burn – 27,500 psi, 1,109 fps, 96.2%F, 88%B
Chronograph Readings: 994, 1030
Ambient Temp: 40F
Group Size: 2” group @ 80yd, bullet stabilized.
Cycle Action: Ejects brass, but would not pick-up next round (close), no lock back.
Third round wouldn’t chamber.. Bell further, scraped lube to case mouth. Revisit this load as it was very clean.
Move up to 24gr and try again.
Load 6 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 20.5g VV N120C
QL Predicted Pressure, FPS, %Fill, %Burn – ~26kpsi, 1,000 fps, 97.3%F, X%B Paper got wet.
Chronograph Readings: 961 (only loaded one), clean, other got wet.
Ambient Temp: 40F
Group Size:
Cycle Action: No, but ejects brass and cocks hammer, not far enough back to pick up next round, no lock-back.
Note….Come back to this one and go up to 21.5g, QL says 21.5=1,084
Load 7 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 22.9g RL7
QL Predicted Pressure, FPS, %Fill, %Burn – 29,000psi, 1,120 fps, 93%F, 89%B
Chronograph Readings: 1,025; 1,035
Ambient Temp: 40F
Group Size: 1” at 80yd. Stabilized.
Cycle Action: YES! Ejected and loaded next round, locked back.
Clean firing, tight group, cycles action firmly unsuppressed. Step up to 23.5g next loading…try to find 1,100fps.
This one is looking good. Will focus here.
Only surprise I had on the above loads was how much louder the loads that opened the action were compared to the early Tin-Stare (N32C) and Trailboss loads that did not open the action. Definitely developing an ear for how far an AR action opens based on how loud it is when dealing with subsonic.
More to come…just got in the 405gr Oregon Trail Laser cast, have not loaded yet.
However, I think to get enough backpressure with slower powders the 500grain range projectile will be required.
When my suppressor comes in I will be posting more data back to this post.
Let me know if there are other combinations I should consider. I have just steered clear of the 500gr jacketed .458 due to the sizing effort I think will be involved as well as the limited opportunity for any expansion.
I need to get some gel and fire a couple of the lead 510hs into them at 1100fps to see if it does anything, but I don’t expect much with regards to expansion.
Thanks,
Herk
About the same time I was working up this post in Word I saw the post by Rklenke, good post bud, going to pick up some of that Shooter’s World Blackout if I can find any.
I do a lot of night hog hunting throughout the year and would like to have a heavy and viable round that is subsonic. I figured if the .458 SOCOM could do it, so can we.
I do not want to pay for some designer bullets aka Black Butterfly.
http://www.450bushmaster.com/viewtopic.php?f=5&t=16120&sid=6db26b5d703dfc8474e066907443896d
I love large calibers and the heavy bullets that go along with them.
When I look around different forums I see a smattering of people searching for heavy bullet data for the .450 Bushmaster but it is a hunt and peck search still for this “young” caliber.
USE AT YOUR OWN RISK, this goes without saying and I appreciate any challenges to data in this experimental area:
I do not want to change springs unless it comes down to a requirement. (as of 3/22 I am still waiting on my suppressor but will go back and edit results as such, guessing July before I get it, .45 HYBRID).
Firearm: 16”, 1-24 Twist, Home Built, .451 slugged.
May be adding a 1:16 AR-556 18” Ruger for my daughter. But using the above for testing because I figure if a 1-24, 16” stabilizes the bullet, then the 1-16 will do so as well. Mid-length Gas system.
According to velocity calculators the 1-24 will have a gyroscopic stability (SG) of 1.47 at 1,080fps when firing our upper end of bullet weights…525 may be a push. This is at the upper end of marginal stability as an SG of 1.5 is recommended, so we will need also indicate in the loads if the bullet keyholed. A 1-16 barrel will give an SG of 3.32 with the same data as above, So the 510 Hunter Supply will act as my focus. This is a readily available cast bullet as I do not cast or powder coat my own.
I have .454, .452 and .451 swagers. Jacketed bullets are brought down in three steps, Cast in two.
Due to readily available, I purchased the following projectiles.
1. “350 OT” - 350Gr Oregon Laser Trail - .452 - .921 Long after sizing (LAS)
2. “400 Speer” - .4515 - .987 LAS
3. “405 OT” - 405Gr Oregon Laser Trail - .452 – 1.025 LAS
4. “405 BT” - 405g WFNGC Beartooth – On Order (reading varying opions on firing through a Supressor, seems like a potentially bad idea to me).
5. “510 HS” - 510Gr RNPB Hunter’s Supply - .452 - 1.34 LAS, These actually weigh about 512gr on average. Do not seat these past a COL of 2.236 (in my rifle), as the bullet will hit the lands.
6. “525 BT” - 525g WFNGC Beartooth Piledriver - On Order
Powders Avaialble:
IMR4198, IMR4227, Trailboss, AA 2015, AA 2495, VVN120C, VVN32C (Tinstar), Lil’Gun, MP300, 296, BLC-2, H380, H414, RL7, lots of others and shotgun powders (Wife says the basement looks like a Cabelas).
Have lots of other powders if you think there are other viable alternatives for good fill and burn percentages. Obviously we have very different powders to push a 200gr vs a 525gr!
As a side note, I find it amazing that this cartridge can push a 180gr projectile up to a 525gr projectile (albeit has its sweet spot). Again, I stress to anyone, that this is a highly experimental area and to validate and use any of this data at your own risk. Like anything on the internet, VERIFY!
In the loads below I did not have any noticeable case head growth, so I did not record it.
Even in the 400gr supersonic load below I had no discernable case head growth deviation from normal, probably because I am only aiming for the 40kpsi line or below.
For all loads below:
Brass: Starline Brass used in all loadings @ 1.69” case Length
Primer: Rem 7 ½ used in all loadings unless noted
Crimp: .4755 Taper and Stab Crimp Placed in an available Cannelure.
For the QL data, I resized the 400g Speer for most and checked by resizing the 500gr .458 down to .452 (Cast) or .4515 (Jacketed). Brass held 61g of water, So a lot of loads came in under what QL predicted from a default of 60g of water.
Load 1 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 350g OT
Powder: 13.5g - Trailboss
OAL: 2.13
QL Predicted Pressure, FPS, %Fill, %Burn – 27,849 psi, 1,076 fps, 96.3%F, 100%B
Chronograph Readings: 1080, 1060, 1073 SD: 10.1
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, Very Clean, very very quiet and light recoil. Would be GREAT in a bolt gun for a kid or if you don’t mind manually cycling an AR.
Load 2 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 350g OT
Powder: 14g Tin Star
OAL: 2.13
QL Predicted Pressure, FPS, %Fill, %Burn – 31600 psi, 1,082 fps, 74%F, 100%B (Under 80% Fill)
Chronograph Readings: 1124, 1130 SD: 4.2 (Only picked up two on chrony)
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, very very quiet and light recoil. Clean Load, would be GREAT in a bolt gun or for a kid, trailboss above was cleaner in Load 1.
Trailboss is right in the wheelhouse for a 350g bullet at subsonic.
Load 3 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 400g Speer
Powder: 15.5g Tin Star
OAL: 2.17
QL Predicted Pressure, FPS, %Fill, %Burn – 39,650 psi, 1,078 fps, 84%F, 100%B
Chronograph Readings: 1061, 1083, 1068 SD: 11.2
Ambient Temp: 40F
Group Size: 1.5” @ 80Yd, Bullets stabilized,
Cycle Action: No, Bolt Barely Moved, Manual Extraction Easy, very quiet and light recoil.
Very Clean Load, would be GREAT in a bolt gun or for a kid.
TrailBoss was tested under a 400g Speer, but only reached 880, 860, 870…did not cycle.
Conclusion…this would be my go-to in a bolt gun for subsonic with Tin Star and 400g.
Maybe a suppressor will add enough back-pressure to cycle.
Load 4 – Fired (Not Attempting Sub-sonic), no sup., just looked like a good combo to zing a 400gr bullet.
Bullet: 400g Speer
Powder: 35g AA 1680
OAL: 2.17
QL Predicted Pressure, FPS, %Fill, %Burn – 39,633 psi, 1,584 fps, 88.7%F, 92%B
Chronograph Readings: 1490, 1460, 1477 SD: 15
Ambient Temp: 40F
Group Size: 1” Group…Very Clean, good well balanced load. Darn good Heavy Load, Bullet Stabilized. Replicates ~4570 light loading in recoil.
This may be a new go to load to add to my 275gr barnes and 200gr barnes!
Cycle Action: Yes, With Authority. Lots of room to go with this in a bolt gun I believe.
Case head growth - NO.
For the loads below…FOCUS Projectile.
Bullet: 510gr HS. 1.34” Long,
Case: 1.69”
All below OAL: 2.235”
QL Predicted Pressure, FPS, %Fill, %Burn: Options Below
Removed SD as I only loaded 2 rounds per loading due to expense and first round pass to see if action would cycle or bullet would stabilize.
Important Note on Crimping: As you can see the 510grn projectile is seated deeper then where it is at .452" so you MUST adjust your taper crimp to just bring the case mouth down to .475 with very little pressure from the press. Then you have to use a stab crimp in an appropriate groove. I chose the middle groove, no particular reason its just where it fell on my blocked up Legendre Crimp setup with a spacer.
510 Grain Hunter's Supply seems to be the ticket, but what a beautiful monstrosity! (Beauty is in the the eye of the beholder).
Load 5 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 22g IMR 4198
QL Predicted Pressure, FPS, %Fill, %Burn – 27,500 psi, 1,109 fps, 96.2%F, 88%B
Chronograph Readings: 994, 1030
Ambient Temp: 40F
Group Size: 2” group @ 80yd, bullet stabilized.
Cycle Action: Ejects brass, but would not pick-up next round (close), no lock back.
Third round wouldn’t chamber.. Bell further, scraped lube to case mouth. Revisit this load as it was very clean.
Move up to 24gr and try again.
Load 6 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 20.5g VV N120C
QL Predicted Pressure, FPS, %Fill, %Burn – ~26kpsi, 1,000 fps, 97.3%F, X%B Paper got wet.
Chronograph Readings: 961 (only loaded one), clean, other got wet.
Ambient Temp: 40F
Group Size:
Cycle Action: No, but ejects brass and cocks hammer, not far enough back to pick up next round, no lock-back.
Note….Come back to this one and go up to 21.5g, QL says 21.5=1,084
Load 7 – Fired, No Suppressor / Suppressor Data When It Comes
Bullet: 510Gr Hunters Supply
Powder: 22.9g RL7
QL Predicted Pressure, FPS, %Fill, %Burn – 29,000psi, 1,120 fps, 93%F, 89%B
Chronograph Readings: 1,025; 1,035
Ambient Temp: 40F
Group Size: 1” at 80yd. Stabilized.
Cycle Action: YES! Ejected and loaded next round, locked back.
Clean firing, tight group, cycles action firmly unsuppressed. Step up to 23.5g next loading…try to find 1,100fps.
This one is looking good. Will focus here.
Only surprise I had on the above loads was how much louder the loads that opened the action were compared to the early Tin-Stare (N32C) and Trailboss loads that did not open the action. Definitely developing an ear for how far an AR action opens based on how loud it is when dealing with subsonic.
More to come…just got in the 405gr Oregon Trail Laser cast, have not loaded yet.
However, I think to get enough backpressure with slower powders the 500grain range projectile will be required.
When my suppressor comes in I will be posting more data back to this post.
Let me know if there are other combinations I should consider. I have just steered clear of the 500gr jacketed .458 due to the sizing effort I think will be involved as well as the limited opportunity for any expansion.
I need to get some gel and fire a couple of the lead 510hs into them at 1100fps to see if it does anything, but I don’t expect much with regards to expansion.
Thanks,
Herk