Joined
·
11,788 Posts
A very hard hitting hog rifle using the 110gr Barnes TSX at 2800fps!! Tosses the 130gr MK319 80fps faster than the Hornady 6.8 120SST with better barrier defeating performance when needed.
Many of us have been talking about this cat for years. I decided to go ahead with it since many like the 30 cal bullets and it's based on the 6.8SPC case. This cat will be very close to Marty Terweem's 30HRT. Both use available 30 Herrett dies. The only difference is in the freebore length and the trim to length of the case. 1.580 is the length to the wall, 1.570 is trim to length. The shoulder is 30 degrees. The shorter case length I use allows all of the 125 and 130gr bullets to be used correctly positioned in the freebore of the chamber. The barrels have the same 1 in 11.25 twist 5R rifling that the 308 barrels have. For plinking or volume loading the 147gr FMJs will be cheap. The 30HRT and 30 Herrett AR will push bullets apx 200 fps faster than the 300 BLK for those intending to hunt deer and hogs.
IMO this is easier to tune loads and find accuracy than the 6.8 however, this is not the best cartridge for someone just learning to reload. Best results will be seen when the case neck is turned to a consistent thickness from mouth to shoulder(especially with SSA brass). The brass shoulder needs to be sized close to the chamber size, do not just screw the resize die down to the shell holder. The brass does not have to be fireformed but maybe a good idea when loading near max charges.
Suggested loads with SSA brass
125gr Sierra prohunter loaded to 2.240-30.5gr 1680=2610fps CCI 450 primer
125gr Nosler Ballistic tip loaded to 2.3"-30.5gr 1680=2680fps CCI 450primer
110gr Barnes TSX loaded to 2.295, 31gr 1680=2678fps
110gr Barnes TSX loaded to 2.295, 32gr 1680=2796fps
130gr MK319 2.290" OAL --30gr 1680 -2530fps-Federal brass load
130gr MK319 bullet loaded to 2.295 30.5-30.7gr 1680=2600fps
The BC of the MK319 is .277 G1
The Hornady 125gr SST is not as accurate as the bullets above.
Added- Using SSA brass. Federal brass has .8gr less capacity.
28.5gr 1680 behind a 125 TNT hit 2500fps out of a 16" barrel.
29.5gr 1680-apx 2570- accurate with 125gr Speer TNT and Hornady SST
30gr 1680=2594fps--54925psi
30.5gr 1680 =2655 --57053 psi max(meaning do not try or use more powder than this)
30.5gr 1680 is pretty much max with 125gr bullets. The 125 Sierra prohunter hit 2600+- and the 125 Nosler hit 2680 with the same charge. The Sierra has more bearing surface, may be why it was slower.
155Amax-30gr AA2200-2367fps-58272psi max-start 2 gr lower
28gr 1680-150 Nosler BT 2399fps-16" production barrel. That is a warm load but no cratering or flattening of CCI450 primers.
That is apx the same as a 24" 30-30 or 200fps faster than a 16" 30-30. I'm impressed.
The Hornady 155 Amax is the same length as the Nosler and will work.
There are a lot of bullets shorter than the Nosler that will work in this case. I think this thing would make a pretty hard hitting hog cartridge and the 147 and 149gr fmjs reduce the plinking cost.
Many of us have been talking about this cat for years. I decided to go ahead with it since many like the 30 cal bullets and it's based on the 6.8SPC case. This cat will be very close to Marty Terweem's 30HRT. Both use available 30 Herrett dies. The only difference is in the freebore length and the trim to length of the case. 1.580 is the length to the wall, 1.570 is trim to length. The shoulder is 30 degrees. The shorter case length I use allows all of the 125 and 130gr bullets to be used correctly positioned in the freebore of the chamber. The barrels have the same 1 in 11.25 twist 5R rifling that the 308 barrels have. For plinking or volume loading the 147gr FMJs will be cheap. The 30HRT and 30 Herrett AR will push bullets apx 200 fps faster than the 300 BLK for those intending to hunt deer and hogs.
IMO this is easier to tune loads and find accuracy than the 6.8 however, this is not the best cartridge for someone just learning to reload. Best results will be seen when the case neck is turned to a consistent thickness from mouth to shoulder(especially with SSA brass). The brass shoulder needs to be sized close to the chamber size, do not just screw the resize die down to the shell holder. The brass does not have to be fireformed but maybe a good idea when loading near max charges.
Suggested loads with SSA brass
125gr Sierra prohunter loaded to 2.240-30.5gr 1680=2610fps CCI 450 primer
125gr Nosler Ballistic tip loaded to 2.3"-30.5gr 1680=2680fps CCI 450primer
110gr Barnes TSX loaded to 2.295, 31gr 1680=2678fps
110gr Barnes TSX loaded to 2.295, 32gr 1680=2796fps
130gr MK319 2.290" OAL --30gr 1680 -2530fps-Federal brass load
130gr MK319 bullet loaded to 2.295 30.5-30.7gr 1680=2600fps
The BC of the MK319 is .277 G1
The Hornady 125gr SST is not as accurate as the bullets above.
Added- Using SSA brass. Federal brass has .8gr less capacity.
28.5gr 1680 behind a 125 TNT hit 2500fps out of a 16" barrel.
29.5gr 1680-apx 2570- accurate with 125gr Speer TNT and Hornady SST
30gr 1680=2594fps--54925psi
30.5gr 1680 =2655 --57053 psi max(meaning do not try or use more powder than this)
30.5gr 1680 is pretty much max with 125gr bullets. The 125 Sierra prohunter hit 2600+- and the 125 Nosler hit 2680 with the same charge. The Sierra has more bearing surface, may be why it was slower.
155Amax-30gr AA2200-2367fps-58272psi max-start 2 gr lower
28gr 1680-150 Nosler BT 2399fps-16" production barrel. That is a warm load but no cratering or flattening of CCI450 primers.
That is apx the same as a 24" 30-30 or 200fps faster than a 16" 30-30. I'm impressed.
The Hornady 155 Amax is the same length as the Nosler and will work.
There are a lot of bullets shorter than the Nosler that will work in this case. I think this thing would make a pretty hard hitting hog cartridge and the 147 and 149gr fmjs reduce the plinking cost.
Starting the tests-16" barrel These loads are near max for one reason or another. Start 1-2gr lower and work up.
29gr Re7-149gr FMJ 2.295=2470fps Max load due to fill
30gr 1200r------------------=2440
30gr 2200-------------------=2426
31gr 2200-------------------=2510--starting to crater ...MAX LOAD
Seeing this with the 150 shows me there is no need to try 4198, N200 or 4227 with bullets near 150gr.
33gr 2200 behind a 125gr TNT at 2.295=2660. Max load due to fill, no cratering or swipes
27gr RE7 or 4198 is max fill. Both of those loads shot the 110gr TSX loaded to2.3" under an inch today. The TSXs IMO shoot better than the 125SST or 125TNT with every load I have tried.
MK319 130gr ammo shot out of a 14" 308 SCAR only hits 2700fps. The 30 Herrett will hit 2600 with a legal 16" barrel(30.6gr 1680). That IMO is pretty close for a small frame rifle VS a full size rifle.
There is a little more difference as the bullet weight moves up to 147gr. 2500 for the Herrett VS 2700 for the 308 both using 16" barrels.
Ballistics Results -125gr Nosler BT at 2600fps
29gr Re7-149gr FMJ 2.295=2470fps Max load due to fill
30gr 1200r------------------=2440
30gr 2200-------------------=2426
31gr 2200-------------------=2510--starting to crater ...MAX LOAD
Seeing this with the 150 shows me there is no need to try 4198, N200 or 4227 with bullets near 150gr.
33gr 2200 behind a 125gr TNT at 2.295=2660. Max load due to fill, no cratering or swipes
27gr RE7 or 4198 is max fill. Both of those loads shot the 110gr TSX loaded to2.3" under an inch today. The TSXs IMO shoot better than the 125SST or 125TNT with every load I have tried.
MK319 130gr ammo shot out of a 14" 308 SCAR only hits 2700fps. The 30 Herrett will hit 2600 with a legal 16" barrel(30.6gr 1680). That IMO is pretty close for a small frame rifle VS a full size rifle.
There is a little more difference as the bullet weight moves up to 147gr. 2500 for the Herrett VS 2700 for the 308 both using 16" barrels.
Ballistics Results -125gr Nosler BT at 2600fps
| Range (yards) | Velocity (fps) | Energy (ft.-lb.) | Trajectory (in) | Come UP in MOA | Come UP in Mils | Wind Drift (in) | Wind Drift in MOA | Wind Drift in Mils |
| Muzzle | 2600 | 1876 | -2.4 | 0 | 0 | 0 | 0 | 0 |
| 100 | 2364 | 1551 | 0 | 0 | 0 | 0 | 0 | 0 |
| 200 | 2141 | 1272 | -3.8 | 1.8 | 0.5 | 0 | 0 | 0 |
| 300 | 1930 | 1034 | -15.3 | 4.9 | 1.4 | 0 | 0 | 0 |
| 400 | 1733 | 834 | -36.1 | 8.6 | 2.5 | 0 | 0 | 0 |
| 500 | 1552 | 669 | -68.6 | 13.1 | 3.8 | 0 | 0 | 0 |
