Where would you like it? Care for a civil, moderated (as best I can) discussion on the subject?Originally Posted by geargnasher
Much like this one, but a different theme?
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Where would you like it? Care for a civil, moderated (as best I can) discussion on the subject?
Much like this one, but a different theme?
Precision in the wrong place is only a placebo.
No, I don't want a "discussion". I want what 45 2.1, Brad, and I asked for on the thread you closed. The only discussion allowed would bear directly on how to sort out specific problems we encounter at each part of the process of making the documentary. People who don't have real answers can sit still and watch and keep their keyboards to themselves and not derail the thread. No more "Well, I think this" or "I think that" blah blah blah. Just facts, like in Missouri. I believe we were told "no" by those in charge.
Gear
Nobody is going to convince me that all else being equal the twist rate difference between a 12 and 14 twist 30 cal barrel will be the single largest factor in group size at 100 yards.
The twist rate difference between a 14" and 12" barrel, all other things being equal, will be "the single largest factor in group size at 100 yards." if you plan on maintaining the same level of accuracy with cast bullets at 2600+ fps vs 2300 - 2400 fps.
If one is satisfied with just "accuracy" using cast bullets then one can get it with just about any bullet weight from 70 gr to 220+ gr in a .30-06 with a 10" twist. We know that because most do that all the time, at velocities from 800 to 1900 fps. However, if you want that same accuracy at velocities above 1900 fps then bullet design, casting, loading and "launching" as close to perfect cast bullets as we can possibly do becomes of paramount importance. The reason being is just above 1900 fps in a 10" twist barrel the RPM generates enough centrifugal force to adversely affect any imbalance in the bullet in flight. You can strive for cast bullet perfection and launch or you can slow the twist down to keep the RPM under 140,000.
Yes that requires a different barrel. But if building a cast bullet shooter why not consider the slowest twist that will properly stabilize the chosen cast bullet? Note here there is a difference between minimal stabilization and "stabilized" as far as twist rate goes. The idea that a slower twist some how limits you to just the one cast bullet and some how is not "versatile" is mistaken. I can still shoot 70 - 200 gr cast bullets with very good accuracy in a 14" twist .308W. The 160 gr 311466 is my bullet of choice for that rifle but an 18: twist would still stabilize that bullet at the 2600 fps I shoot it at. Thus the 14" twist keeps the 311466 under 140,000 RPM and stabilizes the heavier 311299 at 2400 fps quite well. If there is a "limitation" or non versatility it is with lighter weight bullets. A 122 gr 311465 can be pushed to 3000+ fps in that rifle. However, it also loses accuracy at just over 2700 fps. Why? because that is where it approaches 140,000 RPM and it is being accelerated very hard.
That is why I'm getting a 16" twist barrel of 26-28" length (very hard to find one available) for my own 30x57 for use with the 311466 or the LBT 30-160. I want to push 2800+ fps and need to keep the RPM under 140,000. Both of those bullets will be fully stabilized in the 16" twist BTW. No, it will not stabilize the 200 gr bullets but if one wants to dance one has to pay the band. In this case I have no need for any cast bullet over 160 gr as I have numerous 10 and 12" .30 caliber rifles to use those.
One does not buy a 22 Hornet to hunt everything from mice to grizzlies. It is specialized for a specific purpose. So is a slower twist cast bullet shooter. If "versatility was wanted then the concept/conundrum of the "all around" rifle cartridge would have been settled long ago.
Larry Gibson
I did not say that at all. Quite to the contrary I have repeatedly said in these conversations the trick to shooting cast bullets at HV is to launch as perfectly a balanced a cast bullet as possible. A perfectly cast and loaded cast bullet perfectly chambered does not guarantee a perfectly balanced bullet will come out the barrel (at "launch"), especially with the higher psi required for HV. The problem is with HV comes acceleration and the faster we accelerate a cast bullet the harder it becomes to keep the cast bullet perfectly balanced at launch.
The RPM threshold is not "determined by the SYSTEM". Everything that occurs before launch is internal ballistics and it is very important. It is there that the barrels twist will determine the RPM at a given velocity. The RPM threshold is the effect of centrifugal force on the bullet in flight. Centrifugal force is independent of internal ballistics and there is nothing we can do in the "SYSTEM" to change it as it does not occur there. The centrifugal force will act on any imbalance in the bullet (cast or jacketed) during flight. What we can do is influence the imbalances imparted to the cast bullet during casting, loading and acceleration. Thus at the RPM threshold the centrifugal force will cause the bullet to either go off on a tangent from the line of flight or to begin an increasing helical spiral around the line of flight. The degree of either depends on the imbalance and the amount of centrifugal force. In either case the stability of the bullet is not affected. That is during the external ballistics (the bullet in flight) and it is equally as important to understand. We must understand the cause and effect of each ballistic phase in order to succeed.
If we understand where the RPM threshold will most like appear and simply keep the RPM below that we negate the potential adverse affect of the centrifugal force when it reaches the threshold point. That can be done by keeping velocities low with a fast twist or by using a slower twist. In either case we are controlling the RPM which is what allows us the accuracy.
Larry Gibson
Last edited by Larry Gibson; 04-17-2014 at 11:23 PM.
btroj
No, the RPM threshold is not a set limit. We've been through all of that before.
The RPM threshold is seen in jacketed bullets. It's why the Palma shooters when they had to use 7.62 NATO ball ammunition issued by the host nation went to 13 and 14" twist barrels. They did that to lesson the adverse affect the centrifugal force had on the not so well balanced military ball bullets. It is also seen with any long range shooter; they use the best match bullets which are extremely well made and balanced to begin with. Jacketed bullets also withstand acceleration far better than any cast bullet will. Back in the beginning of this discussion several years ago I purpose imbalanced some M118 bullets and shot them demonstrating to bass ackwards that the RPM threshold applied to jacketed bullets too. It does, it is just at a much higher RPM is all. Many times that is above the velocity capability of the bullet in the cartridge used.
Twist rate is indeed a major answer to shooting cast bullets with accuracy at higher velocity. The given the same cast bullet and components a 10" twist will lose accuracy before a 12" twist will and a 14" twist will maintain accuracy to a higher velocity than a 12" twist. This is easily proven with 10, 12 and 14" twist .30 cals. It is also easily proven with 9, 12 and 14" twist .22 cals. I have rifles of each in the same cartridge and prove it over and over again with different cast bullets and powders. If you are building a cast bullet rifle with HV in mind then it would be very prudent to consider the twist unless you are masochistic and prefer a 10" twist. However, if you already have a rifle it is what is and the choices of bullet design, fit, alloy and powder selection become paramount along with a couple other things.
The two phases of ballistics are definitely related but the are also separate. And no, twist rate is not the "whole answer". I never said it was. I have been shooting cast bullets in various twists for a long time. I am not talking theory but facts based on a lot of practical testing of accuracy, velocity and pressures. I am shooting cast bullets at 2600 fps with 1.5 moa accuracy (average) for 10 shots out to 300 yards using the .308W. It is not with a 10 or even a 12" twist barrel. My cast bullets (311466) are of a ternary alloy and are WQ'd. They run 26 - 28 BHN. They are GC'd and lubed with a NRA 50/50 lube or with Lar's 2500+. Bullet design, proper fit and a proper powder are also very necessary.
However, the topic of this thread is "Ideal twist rates" not how to shoot your 10" twist .30 cal at HV. I was discussing the topic, "ideal twist rate", and what twist is ideal. Apparently you're not?
Larry Gibson
Just wanted to say this has been a good thread guys. I picked up on a couple of things here i needed a reminder on. In fact i picked up on several things i've been kind of in a grey area on. I will also say i would love to see a discussion on launch with cast boolits too, as i've already found out the benefits of filling the case with a slower powder lately for a softer launch so to speak. Enjoyed reading this thread very much...Thanks.
Brad, while I agree that twist rate is far from the most important factor, would you not say that for a given load with all it's tolerance stackup, that you could get faster with that load with a 16 twist than a 12 twist? Would the slower twist not take the pressure off a little bit?
What's the disadvantage? Why spin the livin "holy RPM theory batman!" out of it?
That's what I want to know, and my personal interest in this thread. Larry says 16 twist. You say 12. Why 12 and not 14? Why 16 and not 14? Why, in your opinion, must we stay as close to the 12 as possible?
It just seems to me that while shooting a 12 seems more versatile in theory, that the reality would be that the 12 twist is going to be a cruel taskmaster that will beat you to a pulp if you get off the path just a little bit, while the 16 twist would be more forgiving while insisting on speed. Like a stoned racecar driver "its all groovy maaaaan! Just go fast OK, and don't have a cow..." LOL!
I was asked about building a 30XCB by a very special client, and he mentioned that he was considering a 16 twist. I think I told him correctly that that would require him to shoot light boolits fast in order to get good results. had he said he was going for a 12 twist, I would have told him that would require him to shoot heavy boolits slowly in order to get good results. As it was, I told him that I thought that 14 was a good compromise.
Precision in the wrong place is only a placebo.
Btroj
“So to demonstrate the threshold with jacketed you deformed some bullets. Does that not imply that this threshold has something to do with bullet quality? If a bullet needed to be imbalanced to show the effects then the effect on a good bullet must be quite minor.”
That is essentially correct. I induced imbalance into the jacketed bullets (they were of reasonable quality) which lowered the RPM threshold for that particular bullet to demonstrate the non linear effect when a bullet, even a jacketed bullet, exceeds the it’s RPM threshold.
Imbalances are affected by RPM in cast and jacketed bullets. Read post #42 by MtGun44 again. It is excellent and correctly addresses the subject. You might also read the article and look at the pictures about accuracy in bullets in Hornady manuals where the subject is also thoroughly discussed. The centrifugal force of the RPM acting upon the imbalances in the bullet in flight is why we shoot groups instead of all the bullets going into the same hole. There is one other reason but it’s affect is actually quite smaller than many think.
“My point is that when we determine a twist rate it is always better to go too fast than too slow. An I destabilized bullet will never be accurate yet an over stabilized bullet will show, at most, small accuracy disadvantages.”
Here again let us not confuse bullet stabilization with what occurs when a bullet exceeds the RPM threshold. Two completely different phenomenon.
Yes, a “better bullet” can handle RPMs better. As I’ve stated many times the trick to pushing the RPM threshold up is to get that bullet out of the barrel (launched) at HV still in “better” condition. The harder/faster we push a cast bullet the harder it is to do. Thus as Berger correctly states; “the faster spin amplifies inconsistencies in the bullet”. As much as we hate to admit our cast bullets are nowhere near as “better” in balance than a Berger bullet. As much as we try through different alloys, heat treating and now PCing a cast bullet will still not be able to withstand the acceleration w/o deforming that a jacketed bullet will, especially at HV.
The fact is the centrifugal force will always affect a cast bullet more and at a lower velocity/RPM because the cast bullet will probably never be as balanced in flight as any Berger jacketed bullet.
Larry Gibson
BTW; this thread has been informative and a pleasant discussion. I see no need for emotional derogatory insinuations now, do you? Had you read the many posts and even a thread I made/started regarding my Palma loads at 2600 fps you would have all the load detail. I have been very open about it or as they say theses days; "transparent". Also had you read my many recommendations on shooting cast .30 cal bullets at HV you would know I do not recommend 4895 with a Dacron nor do I use it in the 2600+ fps Palma loads. I recommend the slower burning powders such as the one I use in the .308W in the Palma rifle. Your comment is really uncalled for and unwarranted.
You seem to want to rehash the RPM threshold (even though you've come to grips with it's existence) or justify your choice for whatever twist you chose? This thread is about the "ideal twist". I do not espouse the 10, 12, 14 or even the 16" twist as "ideal" because which ever is "ideal" depends on the cast bullet we want to use and the velocity we want to use it at. I use all of them quite successfully and consider each as "ideal" for their intended purpose with certain cast bullets within certain velocity ranges. I do not think there is an "ideal" all around twist. Any of the above twists are going to be "ideal" within certain parameters which they all have. Some are more "versatile than others but they all have a fairly broad range of abilities with different weight cast bullets at different velocity ranges. None of them shoot all weights of cast bullets equally well at all velocities.
So with that in mind and the topic of this thread also in mind can we keep it pleasant?
Last edited by Larry Gibson; 04-18-2014 at 12:57 PM.
Goodsteel
Back to the topic of this thread.
The “ideal twist” for jacketed or cast bullets is dependent on the design and length of the bullet, be it cast or jacketed. However, the term “ideal” is deceptive in that if we do not consider velocity then any twist rate can be “ideal”. For example; a 10” twist ’06. With that we can load a GC’d 118 gr FN at 800 fps and have excellent accuracy. Conversely we can load a 220 gr GC’d cast bullet down to the same 800 fps also with excellent accuracy. But what if we add an additional qualifier of velocity to “ideal”?
Let’s say we want linear accuracy to 300 yards of 1.5 moa or less (I believe some sort of accuracy was already a qualifier of “ideal”?) at 1950 fps? The 220 gr cast bullet will do that easily. However, the shorter and lighter weight 118 gr cast bullet will be very difficult to get there. The velocity will be easy for the lighter bullet but the accuracy will be difficult meet. The reason is the 220 gr bullet is stabilized at that velocity and the lighter, shorter 118 gr is over stabilized. (note; I am not talking the RPM threshold with this example but referencing stabilization) Thus we see the 10” twist is not “ideal” for the 118 gr bullet but probably is for the 220 gr bullet.
If we want a higher velocity then the RPM threshold also comes into play. If we were to have an 18” twist it would be “ideal” for the 118 gr bullet but not good at all for the 220 gr bullet. Thus we see if we are going to discuss an “ideal” twist a couple more parameters are needed.
As to the “versatility” of the 14 and 16” twists. A lot is made of that but in reality it is a moot point. If one is building a cast bullet shooter one needs to make a simple choice; do you want an “all around rifle" for any weight of cast bullet? Or, do you want a specialized rifle for a smaller range of cast bullets at higher velocity?
A 16” twist .30 cal 30x57 will fully stabilize (already done the math) a 190 gr 311334 at 2400 fps, the 30-180 MP at 2200 fps, a 311041 at 2200 fps, a 311466 at 1600 fps, an LBT 30-160 at 1500 fps and a 311465 at 1400 fps. The RPM threshold will probably be 2900+ fps. There is a lot of “versatility” there.
A 14” twist .30 cal 30x57 will fully stabilize (not only done the math but have shot said bullets in my .308W w/14” twist) the 311334 at 2250 fps, the 30-180 MP at 1850 fps, the 311041 at 1700 fps, the 311466 at 1550 fps, the LBT 30-160 at 1450 fps and the 311465 at 1050 fps. The RPM threshold is 2700 fps +/-. A lot of “versatility" there too!
Additionally the 311299 does ok in the 14" twist above 2400 fps. Certainly not "ideal" but ok. It does a lot better both accuracy wise and across a broader velocity spectrum in the 12" twist and may be considered "ideal" for that twist. Perhaps you see what I am getting at; there isn't really any "ideal twist" but in reality "ideal" bullets for a specific twist within a specific velocity range.
I have conducted several tests with different cast and jacketed bullets in .30 cal twists of 10, 12 and 14” and in .223s with twists of 9, 12 and 14”. By measuring the TOF/BC of the bullets (across 100 yards with the Oehler M43) at a given velocity we can compare the stability of the bullets (the higher the BC and shorter the TOF at a given velocity the more stable the bullet is in flight) that each twist imparts. I have related this several times and can again if you are interested. It is an ample demonstration that the “ideal” twist is more of a function of the design and length of the bullet used than anything else.
Larry Gibson
Last edited by Larry Gibson; 04-18-2014 at 02:22 PM.
One good rule of thumb is that "just enough twist" is the right choice for a given bullet and velocity/load range. Its the well established standard in short range BR, and for good reason - decades of empirical data from millions of rounds fired under match conditions. Its been a thorough test of what works on the target and what does not.
I built a BR rifle in a short .308 (like a .30 BR with a long neck) many years ago with a 1-14 twist. It shot 170ish grain boolits very, very well. I could not get the consistency I wanted, but that was a boolit quality problem, not the fault of the rifle. My current .30BR chambered rifle is a 1-18 and shoots light jacketed bullets wonderfully. I've not shot it with lead though - I will have to try that when I get time.
If you're building a purpose built cast boolit rifle, then definitely pick a twist that is just enough and not a whole lot tighter. (i.e. - maximum accuracy at 100 yards with 150 gr. boolits, or 600 yards and 200 gr. boolits)
If you want to shoot a wide variety of projectiles you'll need to pick a twist that is enough for the boolits that require the most stabilization. This necessarily means that the lighter/shorter boolits will get more spin than they need. In that rifle, all boolits may not shoot as well as might be possible under optimum twist conditions for each boolit.
Greetings
Has anyone mentioned gain twist barrels ? To me that is the best there is to come by for us lead shooters. Sadly there are expensive and I understand why.
Then there is the actual rifling shape. Always seemed to me a good solid square edge would "dig into" or grip the boolit far better. That rifling edge the boolit is torqing against is of little help if it is not restaining the bullets twist but due to roundness or sloped less high to permit the boolit to "slip". Seems like that may be why our oversized diameter boolits shoot better. They are under pressure being squeezed into a small hole. By the time they get evened out to groove diameter thay are up to barrel RPM and all is well.
Maybe my problem is I like to have too many shooting sticks to rassle. Should probably sell off the half that are just iffy cast shooters and enjoy the rest of my time with those that really seem to perform. But I would get bored.. no more challenges.
Mike in Peru
"Come unto Me, all you who labor and are heavy burdened, and I will give you rest." Matthew 11:28
Male Guanaco out in dry lakebed at 10,800 feet south of Arequipa.
Rick, I believe the lack of thread drift is that it is hidden in Gunsmithing. Perhaps future discussions on this and similar could be hidden here as well.
[The Montana Gianni] Front sight and squeeze
The RPM Threshold? if that's what you're asking about then I've explained it numerous times in other threads. I really don't want to go there (explanation of the RPM threshold) in this thread unless goodsteel gives the green light. Suffice to say I think the thread is mostly about the "ideal twist" being one that adequately stabilizes the bullet w/o "spin(ing) the livin "holy RPM theory batman!" out of it" as goodsteel put it.
If one is happy with numerous different cast bullets easily and accurately shot at 800 - 1900 fps out of his 10" twist .30 cal then that probably is "ideal" to him. If another is happy with the same but want s to easily reach into the 2300+ fps range with a couple of those cast bullets then the 12" twist is probably "ideal" for him. And if another wants to shoot various cast bullets from 1000 fps to 2600 fps with a couple of them easily and w/o too much trouble or agony then a 14" twist longer barrel is probably "ideal" for him.
Larry Gibson
Last edited by Larry Gibson; 04-18-2014 at 03:30 PM.
forgive me for butting in, but I do find this interesting and at time I think most of you are kinda agreeing on the same thing, your just coming at it from differant angles. Could a chart or grid be made for a say 30 cal. Boolits of 150 - 165 work at fps in given twist, 170- 190 work at fps in given twist, 200- 240 work at fps in given twist. Then we could go on to the hocus pocus of launching the boolit! Tell me to shut up if I am off the wall but I want to learn and at times this almost makes me sit upside down trying to figure you all out! The first time I read this I thought I needed some aspiran afterward!
Look twice, shoot once.
Goodsteel
An interesting side note to consider is that the '06 has a 10" twist because that was what was used with the original 220 gr RN bullets in the 30-40 and the 30-03. When the change was made to the 150 gr M1906 cartridge there was no need to retool because the 10" twist worked ok. Pretty well actually but it was definitelyy known to be lacking in long range capability which is why in the '20s the military went to the 174 gr M1 bullet.
However, during the development of the 7.62 NATO cartridge the bullet weight was settled on 145 - 155 gr with it being a FMJBT. Considerable testing was done with it, the M1 bullet, the tracer bullet and the AP bullet. It was found the 12" twist was "ideal" for all of those bullets out to the expected max effective range of 600 - 1100 meters, depending on bullet. That has especially proven to be the case with BT bullets of 150 - 175 gr weight.
So the "why" and the "difference" between jacketed and cast bullets has more to do with the cast bullet not holding up as well at higher acceleration. The cast bullet just has larger imbalances than do jacketed bullets at the higher acceleration rates and those are accentuated much more at higher RPM of the faster twists. I have gotten a 155 - 160 gr cast to shoot very nicely in my 14" twist because I attenuate the RPM to a lower rate with the slower 14" twist. I do believe that same bullet can shoot just as well at 2700 - 2800+ fps and maybe even 2900+ fps in a 16" twist barrel of a minimum 26" length with the 30x57 or the '06. The reason is the bullet will be fully stabilized yet the RPM is kept below the RPM Threshold. That's why I am willing to put my $s where my mouth is if I can ever get such a barrel(?). I am unable to find one so I guess I'll have to just pick a maker and put my $s down and wait............
Some may get wrapped around the axle over my choice for this based on "lack of versatility" but I think they are just arguing for the sake of just trying to prove me wrong or some other unknown point. I do not intend this to be a "versatile" or "all around rifle". I have plenty of other rifles that can handle the heavy bullets. This rifle is intended strictly for HV cast bullet shooting with the 155 - 160 gr 311466 or the LBT 30-160. This rifles purpose is to see if we can indeed shoot a .30 caliber cast bullet at that high of a velocity with excellent and linear accuracy to 400 - 500 and maybe even 600 yards. It's intended use is simply longer range hunting for coyote and possibly antelope. I have no intention of shooting lighter weight or heavier weight cast bullets.
If the 16" twist barrel does not work in the 30x57 or '06 to expectations then the barrel will be pulled and converted to a .32 H&R Contender Rifle barrel. That twist will be excellent for 70 - 118g cast bullets at 1000 - 1400 fps in that cartridge. In that case I also will be happy with my "versatile 14" twist .30W Palma rifle
Larry Gibson
Last edited by Larry Gibson; 04-18-2014 at 11:32 PM.
That could be done but the length of the bullet is needed for stabilization computation. Also an important consideration is the bullet design for the given cartridge. Some designs are just not suitable to really HV if that's what's interesting to someone.
Larry Gibson
Larry, I am slowly understanding the length thing has a big factor in this also. I guess I think it would be helpful for a chart that maybe would say this specific boolit works best in these given speeds and this boolit works best at so and so. Fortunatly when I started casting I knew to stay slow but I didn't know why. Maybe its wishful thinking but I would love to get all of this threads info in a pratical chart for a newbie or a somebody like me! Keep talking fellas you all have a lot to give,I'm listening!
Look twice, shoot once.
I've always wondered about the old Model 94 Winchesters. The .30-30 Winchester = 1 in 12" and the .32 Win. Spec. = 1 in 16". All other things being the equal for this example, there isn't that much difference in the bullet/boolit diameter, so it must be something else. Smokeless with jacketed vs. black powder and lead and of course projectile design? Any thoughts?
Uber7mm
Bambi: The great American hunting story as told through the eyes of the antagonist.
btroj
"Oh? We need Tim's permission to have thread drift? Wow, didn't know that. Wonder how many other threads ended up with an RPM discussion despite the desires of the OP?"
It's his thread, I'm being polite. Politeness is something commented on here several times. Seems you want to alter the course of the thread.....I don't....comprende'?
I don't think I can buy into a theory that can't be easily defined and explained to me.
I have explained, demonstrated and proved it is not a "theory" over and over for several years now. I could care less whether you "buy into it" at all.....comprende'?
Larry, you say the threshold exists. Others say it is bunk. How are we to know who to believe?
Don't believe the "who", believe the facts and proof. Are you shooting 1.5 moa 10 shot groups out to 300 yards with your 10" twist '06 at 2600+ fps with a cast bullet? If not then you have your proof.
What EXACTLY happens of we exceed the threshold? Does the bullet deform? Is it because the bullet is like a gyroscope and the nose stays in an upward tilt even as the bullet begins to follow the downward portion of its ballistic path?
Just 2 of the many times I've explained it on this forum over the last several years;
http://castboolits.gunloads.com/show...velocity-chart
Post #1
http://castboolits.gunloads.com/show...old-discussion
Post #8
You say that the threshold is determined by velocity and twist, exactly what Tim asked about. You want to separate the discussions even thought they are one and the same.
No, the stability of the bullet is determined by twist and velocity. The twist and velocity also generate RPM but that has to do with the rotational stability of the bullet not the RPM Threshold. As already mentioned, they are 2 different phenomenon. The RPM threshold is determined by the amount of imbalance in the bullet and the centrifugal force at a certain RPM. The greater the imbalance the lower that "certain RPM" will to be. Conversely, the lesser the imbalance in the bullet is the higher the RPM can be. A bullet under or over the RPM threshold still has rotational stability because that rotational stability is not affected by the RPM Threshold. Two different things....comprende'?
That is about all I'm going off track with this discussion on this thread. If you want to further address the issue or if you have specific questions (not challenges) you can PM me or we can discuss it on the other related thread you just started.
Larry Gibson
Last edited by Larry Gibson; 04-18-2014 at 06:58 PM.
Wow, I step away for a few hours and things start going south! Geez you guys!
Brad, quit poking the bear. I want Larry Gibsons opinion, otherwise I would not have started a thread and invited everyone's opinion. The very subject we are discussing is a bedfellow of RPM and external ballistics and Larry Gibson is untitled to his opinion and I want to know what it is.
Larry, thank you for your explanations. I remember the discussion we had on the phone (parts of it anyway. I'm afraid I was suffering information overload by the time we hung up LOL!) and I was hoping you would render what you did in post #77 to the general populace here.
Now, this is a good discussion, and I don't like thread drift when the talk is solid, and I really really frown on folks trying to pick a fight in my living room. Keep it civil fellers. If you've got a problem with someones on-topic opinion here, then take it up in PM and keep that garbage out of my thread. I asked for opinions on this subject, and I don't remember excluding anyone.
That said, I don't want my thread overwhelmed with one persons opinion or agenda either.
How about a little give and take?
Precision in the wrong place is only a placebo.
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