.375 H&H Mag for deer ... mule and whitetail?
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NickEllis
Member
I'm using RL15 and Federal Magnum primers, in Norma brass. So far, so awesome.
Andrew Leigh
Member
300gr. Accubonds in my .375 was more than an absolute pleasure.
Kudu cow, Impala ewe and Warthog sow. All heart shots with what I would call zero meat damage. My other rifles are in danger of becoming safe queens.
Kudu cow, Impala ewe and Warthog sow. All heart shots with what I would call zero meat damage. My other rifles are in danger of becoming safe queens.
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Yet another covert to the no kidding unrelenting usefulness and no nonsense performance on game in real life field conditions. If doesn't matter what it is from elephant to small game the .375H&H kills them cleanly with very little drama. It is simply a very reliable killer with never to much or to little power.
My rife seems to like 270 Barnes TSX bullets over 4895. Plenty of umpf and accuracy.
NickEllis
Member
Yep.
H&Hhunter said:
Hmmm ... it's carrying a lot of velocity and energy at 300 yards with minimal drop. I'd like to see the .308 Win load that produces those results. Seems more like a .300 Win Mag or .300 WSM load with a 100 yard zero to me. Maybe a .300 Win Mag 180gr load.
NickEllis
Member
308win out of a 29in barrel. I'll dig out the full load data when I'm back at the house. Could be I copied down incorrectly, I'll double check.
Pete D.
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velocity
Please do. As noted... that seems like a lot of velocity for that cartridge/bullet combo at that distance.
My little ballistics calculator tells me that that bullet would have to leave the muzzle of the gun at better than 2800 fps in order to have the stated retained velocity.
All of my load books tell me that max velocity for a 200 grain bullet in a .308 win cartridge is just a tad over 2500 fps. Yes, that is from a 24" barrel. Expected velocity gain, though, for a longer barrel is in the area of 5 -10 fps per inch.
Please do. As noted... that seems like a lot of velocity for that cartridge/bullet combo at that distance.
My little ballistics calculator tells me that that bullet would have to leave the muzzle of the gun at better than 2800 fps in order to have the stated retained velocity.
All of my load books tell me that max velocity for a 200 grain bullet in a .308 win cartridge is just a tad over 2500 fps. Yes, that is from a 24" barrel. Expected velocity gain, though, for a longer barrel is in the area of 5 -10 fps per inch.
NickEllis
Member
Checked my data, and first error is obvious: I was shooting the 165gr. Barnes TTSX BT, not the 200. Compressed charge of 46gr. Varget. Average muzzle velocity of 2850fps. Thanks for fact checking me.
I guess it further goes to prove the point, that the venerable .375H&H can perform at similar trajectories/velocities, but with significantly more terminal energy and penetration.
I guess it further goes to prove the point, that the venerable .375H&H can perform at similar trajectories/velocities, but with significantly more terminal energy and penetration.
H&Hhunter said:
I started load development this weekend using the 250gr TTSX from Barnes, Vihtavuori N540 powder, Federal GM215M primers and Remington brass. The first problem is the lack of data for this bullet/powder combination. Barnes has load data for the 235gr and 270gr TSX bullets with N540 and Vihtavuori has data for the Sierra 250gr SBT.
235gr TSX
Min - 76.0gr @ 2,864 fps
Max - 83.0gr @ 3,062 fps
270gr TSX
Min - 72.0gr @ 2,636 fps
Max - 78.5gr @ 2,836 fps
250gr Sierra SBT
Min - 68.5gr @ 2,615 fps
Max - 74.4gr @ 2,808 fps
The first thing to decide is how fast should the 250gr TTSX leave the muzzle. Interpolating the Barnes TSX data gives a maximum velocity of 2,932 fps but that might not be a valid approach. The Sierra max velocity might be more reasonable at 2,808 fps. Anyway, here's some velocity data obtained over the weekend.
Bullet = Barnes .375 cal 250gr TTSX
Powder = Vihtavuori N540
Primer = Federal GM215M
Case = Remington (new)
C.O.A.L = 3.585"
Notes: Case mouth crimped into front cannelure
Rifle - Kimber Talkeetna 24" barrel
Chronograph - CED M2
72.4gr > 2,687 fps (avg of 5 shots)
72.7gr > 2,674 fps (avg of 5 shots)
73.0gr > 2,676 fps (avg of 4 shots)
73.3gr > 2,715 fps
73.6gr > 2,750 fps
73.9gr > 2,757 fps
74.2gr > 2,761 fps
74.5gr > 2,785 fps
74.8gr > 2,777 fps
75.1gr > 2,782 fps
75.4gr > 2,807 fps
75.7gr > 2,812 fps
76.0gr > 2,825 fps
76.3gr > 2,863 fps
76.6gr > 2,869 fps
76.9gr > 2,875 fps
77.2gr > 2,876 fps
77.5gr > 2,887 fps (avg of 7 shots)
77.8gr > 2,888 fps
I shot the first three loads yesterday but the velocity was too low so today I decided to figure out where I need to be with the charge weight to get to 2,850 fps or thereabouts. The 73.9gr to 74.8gr loads made one ragged hole at 100 yards but the velocity is only in the 2,770 fps range so I pushed on. I didn't see any obvious signs of over pressure with any of these loads (primers, bolt lift, O.D. in front of belt). The 77.5 gr load shows promise since loads either side of it had the same POI but after a long day of making loads and shooting prone and 17 bullets sent downrange the best I could do was a 1.4" 5-shot group with that load. I'm going to try three loads of 77.2, 77.5 and 77.8gr and do my usual "round robin" method next time to see if I have an OCW load. The loads listed are probably compressed from 76.0gr onwards and I don't think I can get much more than 77.8gr of powder in the case.
So what should the max velocity of the 250gr TTSX be?
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1858,
There is no 250 gr TSX data, they are recommending that you use the data for the old 250 gr Barnes X. As far as the TSX and increased loads over the Barnes X the TSX supposedly creates less chamber pressure due to reduced surface friction due to the groves. In some calibers the max listed load is 2 to 3 grains over the old non grooved Barnes X. In other calibers it's a grain or 2 less.
Since there is no published load data for the 250gr TTSX you'll have to work up from the old 250 gr Barnes X data. I am at a max load of RE15 via the old 250 Barnes X data currently with the 250 Gr TTSX. I am showing no pressure signs and am also getting about 2850 fps.
There is no 250 gr TSX data, they are recommending that you use the data for the old 250 gr Barnes X. As far as the TSX and increased loads over the Barnes X the TSX supposedly creates less chamber pressure due to reduced surface friction due to the groves. In some calibers the max listed load is 2 to 3 grains over the old non grooved Barnes X. In other calibers it's a grain or 2 less.
Since there is no published load data for the 250gr TTSX you'll have to work up from the old 250 gr Barnes X data. I am at a max load of RE15 via the old 250 Barnes X data currently with the 250 Gr TTSX. I am showing no pressure signs and am also getting about 2850 fps.
Andrew Leigh
Member
1858
This is a first rough pass in QL. If you want me to get you better data I would need the following;
Average case capacity in H20
Exact length of barrel from bolt face to muzzle
Trimmed case length
Maximum magazine length
I have allowed 12fps allowance in drop in MV en route to the chrony hence the 2 900fps on the QL data.
You are well over pressure and your load is compressed more than I would like. Further complications are that I needed to reduce your powder burn rate to calibrate your load which means that you potentially have a slow batch of powder.
I would not continue with this load at present. You maximum safe load is 74.6gr.
This is a first rough pass in QL. If you want me to get you better data I would need the following;
Average case capacity in H20
Exact length of barrel from bolt face to muzzle
Trimmed case length
Maximum magazine length
I have allowed 12fps allowance in drop in MV en route to the chrony hence the 2 900fps on the QL data.
You are well over pressure and your load is compressed more than I would like. Further complications are that I needed to reduce your powder burn rate to calibrate your load which means that you potentially have a slow batch of powder.
I would not continue with this load at present. You maximum safe load is 74.6gr.
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Andrew,
I have QuickLOAD and according to the software, even a charge of 72.4gr is compressed and over pressure showing a velocity of 2,799 fps with a pressure of 63.7 ksi. My actual velocity was 2,687 fps or 112 fps slower. When I input 74.6gr I get a pressure of 70.1 ksi and a velocity of 2,870 fps so not a safe load in terms of pressure. I'll measure the case H2O capacity tonight but I wonder if the velocity discrepancy is due in part to the fact that the bullet is sitting .242" off the lands (see photo below).
The photo below shows the position of the 250gr TTSX bullet when in contact with the lands in the Talkeetna chamber (top) and a loaded round with C.O.A.L. of 3.585" (bottom). The jump to the lands is 0.242".
I have QuickLOAD and according to the software, even a charge of 72.4gr is compressed and over pressure showing a velocity of 2,799 fps with a pressure of 63.7 ksi. My actual velocity was 2,687 fps or 112 fps slower. When I input 74.6gr I get a pressure of 70.1 ksi and a velocity of 2,870 fps so not a safe load in terms of pressure. I'll measure the case H2O capacity tonight but I wonder if the velocity discrepancy is due in part to the fact that the bullet is sitting .242" off the lands (see photo below).
The photo below shows the position of the 250gr TTSX bullet when in contact with the lands in the Talkeetna chamber (top) and a loaded round with C.O.A.L. of 3.585" (bottom). The jump to the lands is 0.242".
Last edited:
Andrew Leigh
Member
I used the load with the 7 rounds as this at 77.5gr. so we need to get on the same page.
Burn rates increase with compressed loads and burn rates increase with increased loads.
PS: You really need to alter to your font size ....... I am 54
.
I can see from the greyed out box on your QL that you have not calibrated your powder?
Burn rates increase with compressed loads and burn rates increase with increased loads.
PS: You really need to alter to your font size ....... I am 54
.I can see from the greyed out box on your QL that you have not calibrated your powder?
Andrew,
I'm simply making the point that even my starting load is over pressure according to QuickLOAD so there's a disconnect between the results provided by QL and my empirical data. No, I haven't calibrated my powder and will have to look into that some more. Thanks for your help ... and I changed the "font".
H&Hhunter,
Thanks for the explanation. Good to see that you're up around 2,850 fps without any issues.
I'm simply making the point that even my starting load is over pressure according to QuickLOAD so there's a disconnect between the results provided by QL and my empirical data. No, I haven't calibrated my powder and will have to look into that some more. Thanks for your help ... and I changed the "font".
H&Hhunter,
Thanks for the explanation. Good to see that you're up around 2,850 fps without any issues.
Andrew Leigh
Member
I have never used QL start load data, I was not aware that they had a start load?
I do not believe that the default is the start load?
I do not believe that the default is the start load?
Andrew Leigh
Member
My routine.
Take powder manufacturers data and start with a safe load.
Chrony and feed into QL.
Calibrate powder burn rate.
Adjust load to meet OBT.
Shoot and recalibrate.
Take powder manufacturers data and start with a safe load.
Chrony and feed into QL.
Calibrate powder burn rate.
Adjust load to meet OBT.
Shoot and recalibrate.
I measured the H2O weight of some new Remington cases last night and the average was 90.7gr with an ES of 0.7gr. QuickLOAD seems to be way off with this one . All of the dimensions are correct but clearly there's something wrong with the powder values. 72.4gr is supposedly way over pressure with a load density of almost 109% and a velocity of 2,885 fps which isn't even close to what I got. I really need to learn how to calibrate the powder.
I did receive a reply from Barnes with load data for the 250gr XFB bullet that they used to make. Max velocities range from 2,767 fps to 2,897 fps with the nine powders listed. They mentioned that they test the 250gr TTSX bullets at around 2,800 fps and that they like Varget for that load. To keep this thread on track I would add that a 250gr bullet with a BC of 0.424 and a MV around 2,800 fps is an impressive projectile. With a 200 yard zero it's 1.6" high at 100 yards and 7.5" low at 300 yards. Even at 400 yards it's "only" 21.8" low with a velocity of 2,086 fps and an impressive 2,415 ft-lb of energy. This probably isn't new to many here but I can' t wait to try this on a big elk and a deer or two.
. All of the dimensions are correct but clearly there's something wrong with the powder values. 72.4gr is supposedly way over pressure with a load density of almost 109% and a velocity of 2,885 fps which isn't even close to what I got. I really need to learn how to calibrate the powder. I did receive a reply from Barnes with load data for the 250gr XFB bullet that they used to make. Max velocities range from 2,767 fps to 2,897 fps with the nine powders listed. They mentioned that they test the 250gr TTSX bullets at around 2,800 fps and that they like Varget for that load. To keep this thread on track I would add that a 250gr bullet with a BC of 0.424 and a MV around 2,800 fps is an impressive projectile. With a 200 yard zero it's 1.6" high at 100 yards and 7.5" low at 300 yards. Even at 400 yards it's "only" 21.8" low with a velocity of 2,086 fps and an impressive 2,415 ft-lb of energy. This probably isn't new to many here but I can' t wait to try this on a big elk and a deer or two.
Andrew Leigh
Member
Hi,
your case volume is remarkably low, I forgot to mention that the volume must be measured in fire formed cases and not cases that have been sized. How did you measure. The volume is one factor that has a large bearing on results so you need to be spot on.
My sequence is.
Start at a safe load.
Head out to the range and pop a couple over the chrony to get an average speed.
Enter all the data into QL.
Now calibrate the powder.
a) Click on the icon directly to the left of the powder selection box. This will un grey boxes to allow you to alter the defaults.
b) Add back the velocity drop to the chrony and make a note of your actual muzzle velocity.
c) Go the Burning Rate Factor and alter this until the speed in QL matches the actual muzzle velocity. In so doing you will have effectively compensated for the component differences, chamber etc. Look on the Burning Rate Factor BRF as a balancing number.
Now I must point out that the BRF changes with charge weigh and case fill AND calibre and bullet choice. so your .375 calibration ONLY works for your current set of components and load.
d) You now need to calculate your Optimum Barrel Time. Google OBT Calculator and download it. Now you will see why I asked you to measure your barrel length accurately. Enter your barrel length into the calculator and you will see various accuracy nodes which are expressed as a barrel time in ms.
Check your existing barrel time in QL and compare it to the calculation. If they are different you now need to calibrate your powder charge.
e)Now alter the charge weight in QL until your OBT in QL matches that in the OBT Calculator. If the accuracy node you selected takes you overpressure then select the next slowest barrel time and recalibrate the powder charge to meet the slower barrel time.
You now have a load according to QL.
f) Back to the range you go to establish what your new average speed is.
Repeat. You normally on head to the range twice unless your initial load was well off the mark.
What I did with my version of QL was to calibrate your powder to your actual results. I used the second highest load as it had seven readings and I always use the highest velocity as the burn rates increase with charge weight.
Now that I have the case volume I will redo the sheet assuming your case volume, that your barrel length is accurate.
Accuracy nodes for a 24" barrel;
Accuracy Nodes
....2...........3...........4............5
0.895....1.022......1.102.......1.228
Now currently you are at 2 900fps actual MV. Calibrating your powder charge throws out immediate warning bells.
- As your measured case volume is small you end up with a fill rate of 116%, methinks not.
- To compensate for this the powder burning rate needs adjusted to a level well below the published burn rate in order to calibrate to 2 900fps.
This all points to the case volume being incorrectly measured.
But for the sake of this exercise lets assume that all data is good.
Now this calibrated load has a barrel time of 1.039ms and is at a pressure of 72 000psi so clearly we need to go slower so lets select Node 4 at 1.102ms. We now later the powder charge until the QL OBT matches node 4.
At 74.3gr we are at 1.101ms but you will note that we are 200psi over pressure. So one would need to decide if the risk of being 200psi is worth it or one would need to go down to the next node.
Currently you are on 62 524psi, 110% case fill and 2830fps.
At this point one could use QL to establish which would be the better powder by clicking the icon with a 1,2 and 3 on it. Click apply and exit and the bottom right screen will be populated with the data. Maximise this screen and your will see that your powder choice is only 5th "best" on the list.
Lets take powder number 2 in the list Alliant Reloader-17. With this combination you get a safer pressure of 59 700psi the case fill is less compressed at 108% and a speed of 2845fps. So clearly this is a better powder for your component combination.
I hope this helps you understand QL better.
I do not trust your case volume.
Cheers
your case volume is remarkably low, I forgot to mention that the volume must be measured in fire formed cases and not cases that have been sized. How did you measure. The volume is one factor that has a large bearing on results so you need to be spot on.
My sequence is.
Start at a safe load.
Head out to the range and pop a couple over the chrony to get an average speed.
Enter all the data into QL.
Now calibrate the powder.
a) Click on the icon directly to the left of the powder selection box. This will un grey boxes to allow you to alter the defaults.
b) Add back the velocity drop to the chrony and make a note of your actual muzzle velocity.
c) Go the Burning Rate Factor and alter this until the speed in QL matches the actual muzzle velocity. In so doing you will have effectively compensated for the component differences, chamber etc. Look on the Burning Rate Factor BRF as a balancing number.
Now I must point out that the BRF changes with charge weigh and case fill AND calibre and bullet choice. so your .375 calibration ONLY works for your current set of components and load.
d) You now need to calculate your Optimum Barrel Time. Google OBT Calculator and download it. Now you will see why I asked you to measure your barrel length accurately. Enter your barrel length into the calculator and you will see various accuracy nodes which are expressed as a barrel time in ms.
Check your existing barrel time in QL and compare it to the calculation. If they are different you now need to calibrate your powder charge.
e)Now alter the charge weight in QL until your OBT in QL matches that in the OBT Calculator. If the accuracy node you selected takes you overpressure then select the next slowest barrel time and recalibrate the powder charge to meet the slower barrel time.
You now have a load according to QL.
f) Back to the range you go to establish what your new average speed is.
Repeat. You normally on head to the range twice unless your initial load was well off the mark.
What I did with my version of QL was to calibrate your powder to your actual results. I used the second highest load as it had seven readings and I always use the highest velocity as the burn rates increase with charge weight.
Now that I have the case volume I will redo the sheet assuming your case volume, that your barrel length is accurate.
Accuracy nodes for a 24" barrel;
Accuracy Nodes
....2...........3...........4............5
0.895....1.022......1.102.......1.228
Now currently you are at 2 900fps actual MV. Calibrating your powder charge throws out immediate warning bells.
- As your measured case volume is small you end up with a fill rate of 116%, methinks not.
- To compensate for this the powder burning rate needs adjusted to a level well below the published burn rate in order to calibrate to 2 900fps.
This all points to the case volume being incorrectly measured.
But for the sake of this exercise lets assume that all data is good.
Now this calibrated load has a barrel time of 1.039ms and is at a pressure of 72 000psi so clearly we need to go slower so lets select Node 4 at 1.102ms. We now later the powder charge until the QL OBT matches node 4.
At 74.3gr we are at 1.101ms but you will note that we are 200psi over pressure. So one would need to decide if the risk of being 200psi is worth it or one would need to go down to the next node.
Currently you are on 62 524psi, 110% case fill and 2830fps.
At this point one could use QL to establish which would be the better powder by clicking the icon with a 1,2 and 3 on it. Click apply and exit and the bottom right screen will be populated with the data. Maximise this screen and your will see that your powder choice is only 5th "best" on the list.
Lets take powder number 2 in the list Alliant Reloader-17. With this combination you get a safer pressure of 59 700psi the case fill is less compressed at 108% and a speed of 2845fps. So clearly this is a better powder for your component combination.
I hope this helps you understand QL better.
I do not trust your case volume.
Cheers
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