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Alpha1 wrote:Some of my club members have acquired new toys. They want to shoot them on our MOD (Ministry of Defence) range days. I dont shoot HME (High muzzle energy) rifles and I am not A HME Range Conducting Officer.
Can any one educate me as to what is required to allow HME rifles to be used on MOD ranges.

I am a Club Secretary no body has demanded any thing. I am trying to understand the requirements to enable my members to shoot HME on MOD ranges its as simple as that.

TRG-22 wrote:Sanity check of my maths - do these figures look right, if you interpolate any mass/velocity figures you know?

No, they don't look right.

A 150 gr projectile achieves 4500 joules at about 3155 fps. Your chart shows it at more than 3750.

I guess the yellow is supposed to be the HME area (> 4500 joules), and therefore the x-axis units are joules.
The red zone looks like combinations that exceed 10,000 joules - what does that represent? (isn't 7,000 joules the maximum allowed on MOD ranges?).

Here's a chart for comparison - note that it also shows a mv limit of 1,000m/s (approx 3280 fps):

Alpha1 wrote:

Alpha1 wrote:Some of my club members have acquired new toys. They want to shoot them on our MOD (Ministry of Defence) range days. I dont shoot HME (High muzzle energy) rifles and I am not A HME Range Conducting Officer.
Can any one educate me as to what is required to allow HME rifles to be used on MOD ranges.

I am a Club Secretary no body has demanded any thing. I am trying to understand the requirements to enable my members to shoot HME on MOD ranges its as simple as that.

Have a look at the range orders for each available range and see what calibres and ME/MV they have. You may find they don't allow them. The range office will be able to provide you with copies. Infact, they might already do so when you renew your licenses to shoot there each year. I know Altcar provides them.

TRG-22 wrote:
What about superscript -6?

:) I did look for that but couldn't find it. Which is why I stopped at the super2.
And besides I didn't need it for the KE equation.

Mattnall wrote:And besides I didn't need it for the KE equation.

You do if you want to start with grains and feet per second and end up with Joules

TRG-22 wrote:

Mattnall wrote:And besides I didn't need it for the KE equation.

You do if you want to start with grains and feet per second and end up with Joules

All good stuff but none of this helps with how to run a HME session on a MOD range.

Alpha1 wrote:

TRG-22 wrote:

Mattnall wrote:And besides I didn't need it for the KE equation.

You do if you want to start with grains and feet per second and end up with Joules

All good stuff but none of this helps with how to run a HME session on a MOD range.

Iain's post seemed to be perfectly clear on the subject?

Alpha1 wrote:

TRG-22 wrote:

Mattnall wrote:And besides I didn't need it for the KE equation.

You do if you want to start with grains and feet per second and end up with Joules

All good stuff but none of this helps with how to run a HME session on a MOD range.

Indeed not - it's all sprung from my Q about calculating ME in Joules from a bullet weight in grains and a muzzle velocity in ft/s.

But I do need to crave everyone's indulgence for one more post, as I really owe a reply and thanks to rox...

rox wrote:

TRG-22 wrote:Sanity check of my maths - do these figures look right, if you interpolate any mass/velocity figures you know?

No, they don't look right.

No, they don't.

And there's a reason for that.

TRG-22 wrote:Given bullet mass m in gr, and muzzle velocity v in ft/s, muzzle energy in joules is

2mv²e-6

Quite handy how all the various constants combine to .000002

Whoever wrote that was an idiot.

The various constants combine to .000003, not .000002, so it should be 3mv²e-6 not 2mv²e-6.

I have closely questioned the idiot involved, and his excuses were a random jumble of I left it on the bus/the dog ate it/a big boy did it and ran away.

Pathetic.

rox wrote:A 150 gr projectile achieves 4500 joules at about 3155 fps. Your chart shows it at more than 3750.

3 x 150 x 3155² x 10^-6 = 4479


150gr = 0.00971984kg

3155ft/s = 961.644m/s

0.00971984x961.644²/2 = 4494

So it now seems that the idiot didn't think that the rounding he did would make a significant difference to the results, but using 3.01mv²e-6 not 2mv²e-6 produces, with your example, 4494 not 4479.

rox wrote:I guess the yellow is supposed to be the HME area (> 4500 joules), and therefore the x-axis units are joules.

Yes and no - the yellow highlighting is >4500J, the X axis is feet per second.

rox wrote:The red zone looks like combinations that exceed 10,000 joules - what does that represent? (isn't 7,000 joules the maximum allowed on MOD ranges?).

The red zone is indeed >10kJ.

And here it would seem is convincing evidence that the idiot's idiocy knows no bounds, for what he did was to look at the FCSA ME limit for visitors and guests at any FCSA range booking, which is 10,000 foot-pounds.

Be assured that I have given him a good kicking, and he is now whimpering in a darkened room.

I have now taken charge of his spreadsheet, corrected the formula, and changed the red highlighting to >7kJ, although I've not been able to find out if there is a blanket limit, or if it varies from range to range. The 10,000 ft-lb threshold for all sorts of restrictions related to HO approval of the FCSA club equates to 13,558J, which implies that there must be some MOD ranges where >7kJ is allowed. Which may explain why the FCSA only list a small subset of MOD ranges as ones where their members can shoot. The Wikipedia article on .50BMG lists example MEs of 13,310 - 14,895 ft-lbs, 18,010 - 20,195 joules.





Lastly, I asked the idiot what he said to the nice man who checked his work and he said "thank you".

Ok, on MoD gallery ranges, firearms with a ME between 4500J and 7000J have to go through the HME zero procedure at the start of the shoot, this must be overseen by an RCO with the HME bolt on.

I have not seen a gallery range cleared for above 7000J, but have never really looked.

On LFTTA's no HME zero is required and any firearm within the limitations of the range can be used, (ie Lydd serial 45 is 1,000m/s and 12.7mm) As there is no HME zero an HME RCO is not required.

Private ranges radnor/orion/eskdalemuir/roundhouse etc. All firearms up the the range limits are permitted, no HME zero procedure is required.