375-408 CheyTac (Kirby Alert!!!!!!) question

[triggerfifty]

hi Dave,

I remember something about that period of time. There is more to it than that, you know there is. Warren Jensen has been fired and bounced out of the company. I walked away, he is in hiding right now from warrants, another subject.

The reality is this, if you were going to make the bullet, it was a patent violation, something few don't take seriously. Reality is this, most wouldn't know how to knock it off and it would fail, then the cheytac name would be #@#$% because the knock off artist would go underground and hide. Not meaning you necessarily here. You know what I mean. A couple have tried to knock it off, not successful, you can't just copy dimensions, the rod material is proprietary.

To no one in particular. The internet crowd has not inherent right to do anything they want with data, knock it off or not, propogate BS or not, make false or misleading statements or not. That's why major companies WILL NOT deal on these websites as a matter of policty. It's a minefield for a company because anyone can wreck a reputation by propagating false stuff. Come to Idaho and i will show you now these solids will shoot, known distance or otherwise.

I am having a long range challenge shoot here on the 7-8 Oct. Unlimited class starts at 1300 yards unknown distance. Sounds like a class for the 338 Snipe-Tec or whatever you are calling it. It's a 408 necked down to 338, just like the 375 SOE is a 408 necked down to a better bullet by far.

Got a good prize table!?

Respectfully,
Dean

PS, i'll pay your entry fee.

SOE Long Range Challenge

 

[lerch]

While I may not be a smart man I still havent seen where you ever answered the initial question of the bullet A passing bullet B with all other things being equal besides starting velocity. Again it is not overly hard to confuse me so maybe I missed it but it seems like mostly you are just talking up the LRBT bullets, something you are saying companies wont do for PR reasons on forums like this and others.

I am not wanting to start a fight here at all, i have really enjoyed this post and I think lots of us have learned a ton from it. As far as the LRBT bullets I aint gonna buy any simply for the price. I will spend the extra amount to shoot custom bullets, hell i have a rifle built around it, but they are asking to much for those suckers. I cannot speak for everyone here but i think those bullets will be a hard sell to most of us, i dont think you can even hunt with them in several states.

Again not trying to start a ****ing contest here just thought i would bounce the original question back at ya.


steve

 

[Fiftydriver]

Lerch,

You are correct, it is simply illegal to use the LRBT J40 bullets for use on game here in Montana and many other western states where an expanding bullet is required.

As such, this is really getting to be a moot point, even if they shoot well, which I know they will in certain barrels but will not in many others, even if they shoot the flattest which they may depending on what they are shot out of, even if they dropped the price for them in half(they would still be the most expensive bullet option), even with all that, it is illegal to use them on game so I guess the question is this,

Get me a bullet that is legal to use on game in that 375 of yours and lets see how it runs with the 338 version. With the current crop of 375 expanding bullets, it will not even be a comparision. Not the fault of the 375, just no bullets out there yet for this type of round designed for our needs.

When Sierra comes out with their SMK it will help alot but still, I suspect a 300 gr 338 SMK will have at least as high, if not higher BC then a 375 gr 375 cal SMK.

Again, we need a legal to hunt with projectile, this is after all Long Range "Hunting". Winning LR competitions is really not high on many of our lists. Very interesting but not what we are really based on.

If you look at LRBT J36 bullets, their highest BC 338 bullet is the 250 gr with a BC of .661. The highest BC 375 J36 bullet is the 300 gr version with a BC of .640.

Neither will come even close to the 300 gr SMK even with a conservative BC of 0.790. I have found its closer to .810 in my rifles over long range. And from what I have read about the field results of these bullets on game, they work the best the harder you push them velocity wise. Similiar to an X bullet but with even less expansion. That means at ranges past 600 yards you would still get pin hole penetration.

I guess after all this discussion we still are left with the problem that there is no use for these bullets in LRH at least legally in many states.

Learning about ballistics is always valuable and this has been a very informative debate. I do not think you have proven your statements about the slower bullets out ranging the faster ones but we all understand that a faster bullet will decelorate at a faster rate then a slower bullet. Same idea why a bullet traveling from 100 to 200 yards will shed dramatically more velocity then the same bullet traveling between the 1500 and 1600 yard markers.

STill we need viable big game hunting options, not mil spec use projectiles. Again, very interesting read but we are comparing apples to oranges again.

Kirby Allen(50)

 

[Black Diamond 408]

First off the bullets i was having made for the 408 was not a knock off from the LRB bullet, it was a totally differnt look and design. He claimed to have the patent for ANY 408 cal bullet...rubish! I had the bullets made but never marketed them. They shot less than .5moa and were a hunting class bullet. They were not designed for extreme ranges, 1500yds was the target area. I explained to Mr. Jensen, the 408 bullets were around long before he came up with his bullets, so a patent on a cal size was crap in my opinon.

On the bbls i use, well lets just say they were special made for the lost river bullets by the specialist you have make your rifles. Like i said they shot ok, but not to the degree i am looking for, i proved it wasn't the bbl's not shooting, it was the bullet. I took 416cal Barnes X bullets and turned them to .4077, we tested them in two different rifles, both had Lawton bbls, that is all i have ever used. The groups with the Barnes bullets were in the .25moa, the LRB bullet from both guns was .7 on average. I am a former bench rest shooter so i am use to guns that have to shoot. Personally, if i cant get close to one hole groups i am not satisfied. I know its harder to get that type of accuracy from the big bores but still i require very tight groups. My customers require very high standards as well, and i will do my best to steer them into the right direction.
Yes the bullets are brass, you know this because i told you this. I have tried the new LRB bullets last winter, they still shoot about the same. The Brass bullets, will out shoot the LRB by half, at a certain distance. I have not done any testing at extreme distances, as i have no reason to do so. I limit most of my testing to 1200yds as my clients are hunters.
Back to the superior 375 bullet, ok what states is it legal for big game hunting? Will it hold .5moa out too 1000yds? If you want your shoot to be real fun, make the targets the same size the 1000yd bench rest clubs use so they can show off the accuracy of the rifles. We are prolly on two different pages of reallity, one a hunting perspective and the other more about sniping. My 338 snipe-tac is what i call it. It is more than a necked down 408 case. It has a special twist that Barney and me came up with, the barrel was ordered in 2001. I designed the new round when i seen the first 408c-t case late 2000. I also worked up drawings for 375 cal, 8mm,416, and a 45cal. I went with the 338 for obvious reasons, the best bullets. The early tests were not all that great. About 1moa was average groups. I went back and changed the reamer specs, cut off the old chamber and re-chambered to the new style, the groups didn't improve. I then looked to bbl problems. I completly relaped the bbl, then re-broke the bbl in using a better method, Moly Powder, the groups emediatly shrunk to .5moa, after 20 rounds the groups kept shrinking. New loads were developed and groups were now in the .100's at 100yds. 500yds 1" groups were seen, 700yds 3"groups, 1000yds 5"groups. This is the kind of rifles my customers are looking for, light weight hunting rigs that will hold tight groupings. I dont doubt Barney's rifles at all, i just have mis givings about the bullets. I hear all the chatter about LRB bullets shooting record groups, but never see them do it. The average guy with a average gun will never get them to shoot. I'm not bashing LRB, its just the facts as i see them through my testing. My 338 will not shoot a LRB bullet, 3" groups is lucky, and it has the special twist that Barney uses on all of the 338 LRB bores. What most guys here will say is, i am not going to build a gun that needs a special bbl to shoot one manufacturers bullets. The average guy is not going to spend 40.00 for a box of bullets and have them shoot worse than a 15.00 box of Hornaday's. Word of mouth is the cheapest form of advertising, it can be a negative one also. Major manufacturers thrive on it, they expect it. They dont like negitive feedback, that is why there is customer suport and services. All i ever got from LRB was its your gun, not our bullets. On a box of 50 bullets i measured 4 different bullet diameters. 75.00 worth of crap!
Don't make excuses, just fix the problem was all i asked. Every one i talked to was having the same results.

I don't doubt any results you come up with, we just want to see some of them. Show us the targets. I know Barney's guns will shoot!

Kirby said it best, this is a hunting site and we need real world hunting type bullets that are legal to do so. This is what i am tring to get across as well.

Take care, all of this is very interesting to say the least.

 

[Brown Dog]

Joining this one rather late,


Nearly spilt my coffee when I read theories along the lines of :

"for 2 identical bullets, the one with the slower MV will overtake the one with higher MV" /ubbthreads/images/graemlins/shocked.gif

For my money Bill Bailey accurately summarised the flaw in the theory:

[ QUOTE ]
The air resistance may be more on the faster bullet, but it still is starting faster. The slower bullet is going 3300 fps @ the muzzle. The faster will be going 3300 fps x # of yds down range. Now, all things are = except the faster bullet has a sizable head start. So, how does the slower bullet make up x # of yds??????


[/ QUOTE ]

....I think people are getting confused by 'averaging' the energy loss figures for the 2 bullets. Yes, taking the muzzle as the start point, over identical distances, the faster one will have a greater average energy loss ....its average will have been skewed downward by the inefficiency of its early flight (when compared to the slower bullet)....it will, nevertheless, always be faster.
/ubbthreads/images/graemlins/smirk.gif


....either that, or we'd better rewrite every artillery firing table ever written...think of all the money that's been wasted putting charge increments in to boost a shell's MV (and therefore range), when we've just learnt here that a lower charge/ lower MV would have made it go further /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/shocked.gif



/ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

 

[wildcat]

This topic continues to be interesting. I am still having a hard time trying to fiqure out how a slower bullet will catch up to the faster bullet. I know science is crazy, but this whole thing about a slower bullet catching up to a faster bullet is not making sense.

Wildcat

 

[Brown Dog]

Wildcat,

Our posts crossed.

You stated:
[ QUOTE ]
this whole thing about a slower bullet catching up to a faster bullet is not making sense.


[/ QUOTE ]

It doesn't, people have confused themselves. Pat yourself on the back /ubbthreads/images/graemlins/smile.gif

 

[waha]

this whole thing about a slower bullet catching up to a faster bullet is not making sense.

Good interesting discussion. I also live in Idaho and have heard the rumors going on down at LRB in Arco.




Except for long bullets not stabilizing due to incorrect barrell twist rate, the only other time I've heard of the faster bullet slowing down more has been documented through the technical term known as "coning". The correct technical term for "coning motion" is gyroscopic precession. This occurs with long, slender, heavy bullets at high velocity starting out partially unstable and not gyroscopically true. In other words if the bullet is wobbling slightly and not true with its geometrical axis due to tipoff forces caused by powder gases escaping through imperfections in the crown, rifling or the surface of the bullet. This is why most B.C.'s are developed at 100 yards or greater because this "Coning effect" is usually over within the first 100 yards but it significantly effects the bullets BC during the first 100 yards or so. In other words the faster bullet that is unstable is slowing down faster than the stable bullet during the first 100 yards. The larger frontal area of the bullet while coning creates more drag and resistance which is reducing speed quicker and lowering the B.C.

I know Sierra, Hatcher, DR. Ken Oehler and others have discussed the effect of "coning" and its effect on the G1 Drag model.

 

[bailey1474]

[ QUOTE ]
....I think people are getting confused by 'averaging' the energy loss figures for the 2 bullets. Yes, taking the muzzle as the start point, over identical distances, the faster one will have a greater average energy loss ....its average will have been skewed downward by the inefficiency of its early flight (when compared to the slower bullet)....it will, nevertheless, always be faster.

[/ QUOTE ]

Now that makes alot of sense. At least to my feeble mind /ubbthreads/images/graemlins/crazy.gif.

 

[Brown Dog]

[ QUOTE ]
In other words the faster bullet that is unstable is slowing down faster than the stable bullet during the first 100 yards. The larger frontal area of the bullet while coning creates more drag and resistance which is reducing speed quicker and lowering the B.C.

[/ QUOTE ]

..well, if we're saying the faster bullet is not stable for it's entire flight, but the slower one is, we're not comparing apples with apples.

(...I've also assumed that the faster bullet isn't being fired base first /ubbthreads/images/graemlins/smile.gif )

...if 2 identical jets are cruising at 500knots and then one employs afterburner for 1 km, the afterburner jet will become less efficient and have increased drag (ie it will have greater energy loss) than the non afterburner aircraft. ...it will, nevertheless, be going faster than the non afterburner aircraft.

....if at that 1km point, with the afterburner aircraft doing, say, an energy inefficient 700knots, and the non afterburner still tootling along at 500kts, both were to cut there engines and glide....the afterburner aircraft may have greater energy loss....but it will always be faster.

Ditto, 2 identical cars on identical surfaces simultaneously passing a fixed point; one at 70mph and the other at 40. The 70mph car will have greater drag and be less efficient. If both cut to neutral and coast, the 70mph car will experience a greater rate of energy loss....but will coast further.

 

[Fiftydriver]

Well, the unstability issue does make some sense as far as a faster bullet being passed by a slower bullet down range. But I assure you it is not hard to build a rifle to fully stabilize or should I say "Correctly" stabilize a bullet at these velocities.

BD408 has tested down to 1-9.25 twist barrels and up to 1-11.25 twist pipes, I use standard 1-10 twist for my 338 AMs.

I personally feel if your going to use a 300 gr SMK, the 1-11 twist may be perfect. You can use a 1-10 like I am and get great results. I personally feel the 1-9 class twists are to fast for anything but a 350 gr ULD RBBT and even then they are not needed as I have shot them in my 1-10 with great results.

We still have not gotten a response about the comparision between the top performing 338 hunting bullet and the top performing 375 hunting bullet when used over a 408 CT class case volume.

I suspect the reason is because there is nothing worth comparing, even with the J36 LRBT bullet in the 375, the 300 gr SMK will smoke it in either the 338 Big Bear, 338 Sniper-Tac or my 338 Allen Magnum.

Waiting with interest about the response from Triggerfifty.

Kirby Allen(50)

 

[lerch]

"Waiting with interest about the response from Triggerfifty"

Me too, I am also waiting for the answer on the slower bullet passing the faster bullet.


still a good topic, man i hope richard gets to making some 338bullets again, i want some of those 350gr ULD's for my 338AM.

steve

 

[Black Diamond 408]

From my testing and that of others, the 300MK will stabilize from 9.5 through 11.5 twists, currently Barney Lawton is using the 11.5 twist rate on the 338 Big Bear bbls. Also the same 11.5" twist is being used on the 375-408 version. This is the heaviest bullet you can put through this twist(300mk). As Kirby has stated, the 10 twist is right in the middle, i see no difference in accuracy from the 9.5 up to my bbl's 11.25 twist, using 300MK's But if you go heavier, the 11" twists will not stabilize the bullets. I built my rifle around the 300MK bullet, I wanted to "spin" the 300MK bullet the same amount a Lapua does at 2900fps, my rifle speed was 3350fps. Running the bullets through the 9.5" twists had the same effect but more spin rate, groups are well under .5moa.

lighter bullets also shoot very well, but impractical unless you want to incinerate what your shooting at. The case capcity is too large for the smaller weights. I wish there was a 325gr bullet, i feel this would be a very good balance for speed and BC. A match-hunting bullet with a BC of .850-.900 surely would extend the range of the big 338's, 2700 yards or more before the transition takes over. Currently the 300MK will put out BC's just over .800 The 350gr Wildcat bullet may very well excede that with more testing, that i can not do in my personal rifle due to the twist rate. The speeds of the 350gr bullets are in the 3200fps range, 338cal. This is where the 338 cal rifle will put down the 375 version, lack of propper hunting bullets. From my calculations, the 300MK will out perform the 350grn bullet to about 1200yds, then the 350gr 338cal bullet will take over for balistics and retained energy. Make no mistake, the 300mk has made numerous Elk kills past 1800yds.

From the desk of a rifle builder, no expert on exterior balistics!

 

[Fiftydriver]

BD408,

I have some wildcat 325 gr FBHPs. THey are a serious looking big game bullet. Richard will be able to make pretty much anything you want once he gets his dies back, 250 up to 350. I am even pushing him to build a 375 gr ULD RBBT in 338. That would put that 1-9.5 to good use!!

Kirby Allen(50)