6.8 minimum velocity

[sharpshooter08]

I apologize in advanced if this is a dumb question.

I was just curious on what the optimum/minimum velocity should be for the 6.8 round. Every where I have read it seems you want to stay above the 2500fps mark to achieve the best ballastics. But looking at the same loading charts I see alot of grains dipping below the 2500fps and even close to the 2000fps mark.

The reason I ask is I want to get into reloading and I have downloaded Tims guide on the laoding data. I was planning on highlighting the the bullets that where above the 2500fps mark as a guide line since Im new to the reloading stage.

Thanks

[paulosantos]

If you mean the minimum velocity in which the bullets will fragment/expand, here are the numbers:

Maximum Performance Range of the 6.8SPC:

1. Hornady 110 Gr. V-Max with a muzzle velocity of 2550 fps (16" barrel), will fragment from 1900+ fps, which leaves a maximum performance range of 305 yards.
2. Hornady 110 Gr. HP with a muzzle velocity of 2550 fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 212 yards.
3. Hornady 115 Gr. BTHP with a muzzle velocity of 2550 fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 220 yards.
4. Sierra 90 Gr. HP with a muzzle velocity of 2900fps (16" barrel), will expand from 2000+ fps, which leaves a maximum performance range of 213 yards.
5. Sierra 110 Gr. Pro-Hunters with a muzzle velocity of 2500fps (16" barrel), will expand from 1700+ fps, which leaves a maximum performance range of 330 yards.
6. Sierra 115 Gr. SMK with a muzzle velocity of 2500fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 192 yards.
7. Sierra 130 Gr. Pro-Hunters with a muzzle velocity of 2400fps (16" barrel), will expand from 1700+ fps, which leaves a maximum performance range of 341 yards.
8. Speer 90 Gr. TNT with a muzzle velocity of 2900fps (16" barrel), will expand from 2000+ fps, which leaves a maximum performance range of 285 yards.

[owenslee]

The Pro Hunters are again an excellent choice over other alternatives for extended down range performance...

Kerry

[rcrandall]

The 2500 fps mark is for full metal jackets for the 5.56mm. Not sure on the 115gr FMJ's for the 6.8.

[TackDriver68]

If you mean the minimum velocity in which the bullets will fragment/expand, here are the numbers:

Maximum Performance Range of the 6.8SPC:

1. Hornady 110 Gr. V-Max with a muzzle velocity of 2550 fps (16" barrel), will fragment from 1900+ fps, which leaves a maximum performance range of 305 yards.
2. Hornady 110 Gr. HP with a muzzle velocity of 2550 fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 212 yards.
3. Hornady 115 Gr. BTHP with a muzzle velocity of 2550 fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 220 yards.
4. Sierra 90 Gr. HP with a muzzle velocity of 2900fps (16" barrel), will expand from 2000+ fps, which leaves a maximum performance range of 213 yards.
5. Sierra 110 Gr. Pro-Hunters with a muzzle velocity of 2500fps (16" barrel), will expand from 1700+ fps, which leaves a maximum performance range of 330 yards.
6. Sierra 115 Gr. SMK with a muzzle velocity of 2500fps (16" barrel), will fragment from 2000+ fps, which leaves a maximum performance range of 192 yards.
7. Sierra 130 Gr. Pro-Hunters with a muzzle velocity of 2400fps (16" barrel), will expand from 1700+ fps, which leaves a maximum performance range of 341 yards.
8. Speer 90 Gr. TNT with a muzzle velocity of 2900fps (16" barrel), will expand from 2000+ fps, which leaves a maximum performance range of 285 yards.



Once again....All Hail Paul

[Float Pilot]

Any ideas on the 110 grain Nosler Accubond? I am launching those (plus the pro-hunters & Barnes trip X) at 2,550 from my 16 inch Stag.

I wish I could get a 130 gran to go 2,400.. So far 2,275fps is all I am really getting...

[paulosantos]

Any ideas on the 110 grain Nosler Accubond? I am launching those (plus the pro-hunters & Barnes trip X) at 2,550 from my 16 inch Stag.

I wish I could get a 130 gran to go 2,400.. So far 2,275fps is all I am really getting...

If the 110 Gr. accubonds expand at 1900+FPS, then they will have the same performance range as the Hornady 110 Gr. V-Max, which is 305 Yards. If they expand at 1700+FPS, the maximum Performance range will be 394 Yards.

[Float Pilot]

I was wondering if anyone knew their expansion velocity....

My personal cut-off for humane hunting is usually 1900 fps at impact, except for cartridges like the 45-70 and 50-90.

[Tim_W]

The Accu-Bonds fully expand down to 1800 and maximum is 3100 where you get jacket separation (fraging). They have a real world BC around .400-.410 measured from actual bullet drop.

The term "ideal minimum performance velocity" is misinterpreted so often and is also rather vague IMO.

Minimum impact velocity for a particular make/type of bullet and its specifc performance goal is what matters. The type of perf goal you have has will also change depending on what you are shooting at. Human, Deer, Ground Hog, Elk, etc..

'MV has no effect what so ever on what the minimum impact velocity is or what the bullet will do at that vel. It only effects the maximum range that minimum impact velocity will be reached at and what will happen with a impact at the higher velocities before this min is reached.

All bullets have a impact velocity range or bracket where the bullet is intended to perform in a particular way based on its makers goal.
Upset, Expansion, Fragmentation, penetration depth, etc..

The 6.8 is capable of significantly higher MV with many of those rounds then in that chart which I know were used to show the relationship. Call me paranoid but I figured we would eventually see a post somewhere by certain detractors that these numbers from Paulo's chart were the ideal (read maximum) MV for the 6.8 with these bullets. That chart will be sitting right next to that same old chart of some low BC 6.8 bullets going slow to show how the 6.8 top traj perf. is only 300 yards :roll: :lol: ) Anyways min impact vel for that particular bullet to achieve a specific type of performance along with MV is needed to compute maximum effective range where that type of terminal performance can be expected.