*NEW* 8mm (.323") Cutting Edge MTH bullets

I don't want to put a dampener on this project but have you ever shot anything with the Cutting Edge MTH projectiles at long range?

I have with a .375 Cheytac and was not overly impressed. While they are super accurate, they simply do not do much damage compared to a traditional bullet.

If you are going to shoot large game at long range with them, expect to loose a few.
 
Something interesting on twist rate and bullet length:

A bullet needs a particular set of circumstances to fly correctly over the entire trajectory from muzzle to target. The stabilty factor is influenced by both the twist rate of the barrel and the muzzle velocity. The most important, by far, is the twist rate of the barrel. To illustrate this relationship, a practical example is given below. Stabillity can be the gyroscopic stabilty (Sg) or the dynamic stability (Sd). Usually when 'bullet stability' is discussed, Sg is intended.

Muzzle Velocity at 1600fps
speed1600.jpg


At a muzzle velocity of 1600fps and a barrel twist rate of 1:10", the stability factor (Sg) is 1.25.

An increase in muzzle velocity results in an increase of the Sg and, going from a muzzle velocity of 1600fps to 3600fps, results in an increase of the Sg to 1.34. The chart below shows a muzzle velocity of 3600fps.

Muzzle Velocity at 3600fps
speedtwist3600.jpg


A difference in twist rate of half an inch, up or down, will influence the Sg as follows: At a twist rate of 1:10.5" and at a muzzle velocity of 3600fps, the Sg is 1.215. At a twist rate of 1:10" the Sg is 1.339.

So, increasing the twist from 1:10.5" to 1:10", increases the Sg by 0.124 and has a greater effect on the Sg than an increase of muzzle velocity from 1600fps to 3600fps. It is quite clear that a twist/bullet length mismatch cannot be fixed by adjusting the speed. A 2000fps increase in speed has less value than a half inch difference in twist rate.

The full text is at GS CUSTOM BULLETS - Twist Rates and Bullet Length
 
Something interesting on twist rate and bullet length:

A bullet needs a particular set of circumstances to fly correctly over the entire trajectory from muzzle to target. The stabilty factor is influenced by both the twist rate of the barrel and the muzzle velocity. The most important, by far, is the twist rate of the barrel. To illustrate this relationship, a practical example is given below. Stabillity can be the gyroscopic stabilty (Sg) or the dynamic stability (Sd). Usually when 'bullet stability' is discussed, Sg is intended.

Muzzle Velocity at 1600fps
speed1600.jpg


At a muzzle velocity of 1600fps and a barrel twist rate of 1:10", the stability factor (Sg) is 1.25.

An increase in muzzle velocity results in an increase of the Sg and, going from a muzzle velocity of 1600fps to 3600fps, results in an increase of the Sg to 1.34. The chart below shows a muzzle velocity of 3600fps.

Muzzle Velocity at 3600fps
speedtwist3600.jpg


A difference in twist rate of half an inch, up or down, will influence the Sg as follows: At a twist rate of 1:10.5" and at a muzzle velocity of 3600fps, the Sg is 1.215. At a twist rate of 1:10" the Sg is 1.339.

So, increasing the twist from 1:10.5" to 1:10", increases the Sg by 0.124 and has a greater effect on the Sg than an increase of muzzle velocity from 1600fps to 3600fps. It is quite clear that a twist/bullet length mismatch cannot be fixed by adjusting the speed. A 2000fps increase in speed has less value than a half inch difference in twist rate.

The full text is at GS CUSTOM BULLETS - Twist Rates and Bullet Length

Thank you for a very impressive description and good advice!
A good and superior rate of twist for the use of modern heavy and long bullets in 8 mm is 1 : 9,45. That's what we nowadays use in Europe concerning 8 mmS/.323 for both standard and magnum cartridges. This twist will stabilize most of the projectiles without any issues with weights up to 230 gr. Bullets with extreme length and weight (256 gr MTH) should have ideally 1 : 8.
 
Here is a comparison pic I took of the new Cutting Edge MTH bullets next to all the 8mm bullets I could find in the past few months...... Have more coming !

Also have reamer on order for my new wildcat the 8mm Razor (8mm/300 RUM Imp 37*) !

Figured if I'm gonna need custom reamer and dies might as well imp the case...... I Set it up with a no turn/no ream neck and to headspace snug after necking up 300 Rum brass to 8mm in order to simplify fire forming, throat set up for the 225 gr & 256 gr Cutting Edge MTH bullets and case h20 capacity at 114.5 gr which is the same capacity as necking down the 338 Lapua case ,
(13-14 gr more than the 8mm Rem Mag......)

I abandoned the 32 Nosler Imp 37* project ( same body dimensions as the Razor except for length) simply because it only produced 102.5 gr h20 case capacity and still needed a Long Action and mostly because I have over 1000 pcs of Rem 300 RUM brass from accumulation over the years of owning several 300 Rums and a 338 Edge rifle, even though Rem RUM brass is scarce, the Norma 300 RUM brass has been available and I've picked up 200 pcs of that stuff from Brian @ Shoot-Long.com .....
Shoot-Long | Norma Reloading Brass 300 Remington Ultra Mag 300 RUM (100 pcs)

The name "8mm Razor" is to complement my 338 Edge rifle with another barrel for a "Razor Edge" hunting rifle,
got my 30" 9 twist Pac Nor barrel pretty quick and it looks sharp with perfect fluting by Pac Nor, ordering another one just like it for my 8mm Long Range Hunter ! Now I Gotta figure out what to do with the new 30" #5 Bartlein 10 twist fluted blank I got for It earlier ....
 

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Hmm, so many bullets to try. So far, I've only used the 200 gr AccuBond. Wish they made a 220.
220 A-Frame might be worth a try.
And the 200 TSX. I've used TTSX in other calibers. They like to go fast, and you typically use slightly lighter bullets than more traditional designs, so 200 may be about right for this one.
500-600 yds is "long-range" for me.
220 gr Hawk should hit like a sledgehammer inside that range in my 8RM. I wanna try 'em.

I'm sure the MTH cruises along as good as any 8 out there. I want to see how they perform on big game before I commit. Almost need a rifle bored specifically for that bullet.
 
Swamp, I understand this thread is several years old, but how did your 8mm projects transpire? I have been looking at the 248gr Hammer Hunters and thinking that an 8mm Ultra would be pretty cool. That is how I stumbled in to this thread.
 
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