Home Forums Hunting & Shooting Handguns ROSS SEYFRIED QUESTION

You guys are mixing way too many variables and making conclusions based on too little information.

First and foremost, the fact that a lighter monolithic outpenetrates a heavier cast does not "destroy" the SD "argument". All it means is that weight moves down the totem pole in favor of a bullet that does not deform.

Second, SD is not an all-encompassing belief system. It's not an argument. Or a measure of lethality. It is simply the bullet's weight relative to its diameter. It is a singular factor among many. I don't know why people are in such a hurry to dismiss it.

We have tons of cast bullets in various weights, so it is easy to determine that heavier bullets of a comparable shape/hardness/toughness will penetrate deeper than lighter ones. However, there are far too few monolithics to be able to even properly compare them and determine what role SD plays.

I would just about bet the farm that a 300gr .500 wouldn't come close to a 300gr .44 in penetration. I've seen this first hand with the additional drag a .45 bullet has over a .44 at a given weight. It will be interesting to find out.

You guys don't think thee's a reason why these bullets are as long as a heavy cast? If weight relative to diameter was not a factor at all, they'd be making these bullets a lot lighter, that could be driven a lot faster. But they are not.

Here's the 270gr Punch, 300gr Punch, 300gr Barnes Buster compared to 330gr LFN and 355gr WLN. If weight doesn't matter, why are they so long???

You guys are mixing way too many variables and making conclusions based on too little information.

First and foremost, the fact that a lighter monolithic outpenetrates a heavier cast does not "destroy" the SD "argument". All it means is that weight moves down the totem pole in favor of a bullet that does not deform.

Second, SD is not an all-encompassing belief system. It's not an argument. Or a measure of lethality. It is simply the bullet's weight relative to its diameter. It is a singular factor among many. I don't know why people are in such a hurry to dismiss it.

We have tons of cast bullets in various weights, so it is easy to determine that heavier bullets of a comparable shape/hardness/toughness will penetrate deeper than lighter ones. However, there are far too few monolithics to be able to even properly compare them and determine what role SD plays.

I would just about bet the farm that a 300gr .500 wouldn't come close to a 300gr .44 in penetration. I've seen this first hand with the additional drag a .45 bullet has over a .44 at a given weight. It will be interesting to find out.

You guys don't think thee's a reason why these bullets are as long as a heavy cast? If weight relative to diameter was not a factor at all, they'd be making these bullets a lot lighter, that could be driven a lot faster. But they are not.

Here's the 270gr Punch, 300gr Punch, 300gr Barnes Buster compared to 330gr LFN and 355gr WLN. If weight doesn't matter, why are they so long???

I agree with all of that. However, only so much rifle ideology applies to handguns because we're operating at 1000fps less. We're getting the same job done with less bullet weight because the bullets do not deform but I do not think that suggests that SD and therefore weight does not matter. They are still relatively heavy bullets. If weight/SD did not matter at all, we would get the same job done with VERY light bullets. There has to be a tipping point. The copper solids don't eliminate SD as a factor, it just moves the scale down. In other words, more information/testing is needed.

In some regards, we are well ahead of the big bore rifle crowd. They're just not figuring out that flat nosed solids work better than round nose. Revolvers are also not limited according to what nose shapes will and won't feed.

This piece below was penned by Michael McCourry, the gentleman who designed the CEB solid. He has killed more bovines in testing than anyone else I know by a wide margin to test his designs and theories. He knows what he is talking about...



There are 8 Absolute Known Factors for Solid Penetration and are as follows in
Order of Importance.....

#1 Meplat Percentage of Caliber
Meplats that attain 65% Meplat of Caliber are terminally stable.... Above 70% Meplat
bullets remain stable, however depth of penetration begins to decrease with every step up in
meplat size. 70% Meplat or larger does increase trauma to, and destruction of tissue. 70%
Meplats start to get difficult to feed, even in Winchester M70s...... From 65% Meplat to 68%
Meplat is OPTIMUM for Stability, destruction of tissues, and feed and function in most quality
rifles..........

#2 Nose Profile
There are many and varied Nose Profiles of solids on the market today, from the angled
Nose Profiles of CEB and North Fork, to the straight nose profile of the older North Forks
and GSC, the Barnes/Hornady Profiles (like a RN cut off at the top) to many more... Not all
of these are created equal, and some are better performers than others. In recent tests in
comparison between the old North Fork Profiles and the Newer North Fork Profiles I was
getting 20% deeper penetration with the Newer North Forks than the older, with the same
bullet, just difference in Nose Profile is all.... John at North Fork agrees, and in their work
there they were getting more along the lines of 25% deeper penetration. One major thing
that I noticed here, the stability at the end of penetration was 100% better. In most all tests
here the last 2 inches of penetration of the old style North Forks would be unstable. Now this
is and was of no consequence at the very end of penetration. The depth of penetration of
these older nose profile bullets was always so deep that it had long accomplished its mission
before loss of stability right at the very end. This new NOSE PROFILE of North Forks remains
DEAD STRAIGHT to the very last of penetration, and always found NOSE FORWARD........

#3 Construction & Material
Construction of a solid is a major part of its ability to penetrate. To deny this is foolish to say
the least. Some of our solids out there, lead core, are very very weak in construction and
absolutely do not have the ability to bust through heavy bone and reach their intended
targets. I have seen and have in hand failures of these bullets from the field..... A shame as
well, as some of these bullets are promoted as Dangerous Game Solids, and some of them
flatten out like pancakes when hitting some heavy..... Some FMJ Have steel inserts, while this
solves a problem in one area, it creates problems in other areas.... Brass is harder than
Copper... No surprise there, but I have busted elephant heads with both copper and brass,
and never had one distort, but, these solids were of a very STRONG NOSE PROFILE as
well........ So you see, combinations of different factors work together to strengthen or
weaken other factors..... A good strong Nose Profile, can overcome some material
deficiencies and in the case of copper solids this is extremely important, and very true........

#4 Nose Projection
Nose Projection above the top bands was the last factor discovered. There may be more
factors, but currently they remain undiscovered at this point in time.... We found that nose
projection above the top of the bands of current CNC monolithic bullets is very important to
depth of penetration. Some bullets designed to work through lever actin riflers require a
SHORT NOSE PROJECTION in front of the bands so that they can be loaded deep enough to
work through the actions of these guns... Nose Projection of these same bullets for bolt guns,
single shots, and double rifles are longer, from .600 to .700 in front of the top band. The
LONGER NOSE PROJECTION solids will penetrate on average 25% deeper than the shorter
nose projection. Now, these bullets already have all the other required factors for stability,
nose profile, construction and radius, so it is ONLY DEPTH Of penetration that is effected with
properly designed bullets.

#5 Radius Edge of Meplat
We found that the radius edge of the meplat made a difference, small, but a difference none
the less. A nicely radius edge penetrates about 5% deeper, and has more stability at the end
than a sharp edged radius.... No more to go into here, thats it.......

All the Above Factors Deal with Bullet Design........

#6 Velocity
Velocity is a factor, but it also goes hand in hand with Nose Profile and Construction/
Material. If we assume that the Meplat is optimum, the nose projection is optimum, and the
bullet has a nice radius then velocity becomes a factor in combination with nose profile and
construction/materials. Different Nose Profiles react differently with velocity. Some nose
profiles at very low velocity cannot maintain stability, but this would be in the extreme, and
other factors may come into play with some of this. In essence with some Nose Profiles,
added velocity will equate to added depth of penetration, and of course trauma and
destruction of tissue. Some nose profiles react better than others, but if properly designed,
then all will get some gain from added velocity, UNTIL you reach the point that you get
distortion of the meplat by TOO MUCH VELOCITY. Once you begin to distort that meplat,
then all sorts of strange things begin to occur. One is depth of penetration will decrease,
stability will decrease as well....... Normally you will only get this at extreme velocities at
2700-2800 fps or more, which in our big bore rifles is somewhat extreme.......... Lead core
bullets will be effected in a serious manner at extreme velocities, followed by copper, and
then brass........ Nose Profile and Construction & Material are very important for Factor
#6.........

#7 Barrel Twist Rate
Barrel twist rate really only becomes a factor when Factor #1 is DEFICIENT....... If the meplat
of caliber is undersized, less than 65%, then faster twist rates WILL INCREASE the depth of
penetration by increasing the stability of terminal penetration. A 65% Meplat of Caliber can
stabilize in slower twist rates of 1:18, or even slower...... I have seen 65% Meplat of Caliber
stabilize with ZERO TWIST....... I have seen 50% Meplat of Caliber stability increase with
faster twist rates, and have documentation to prove it, several times...... If you are using a
properly designed Solid, then twist rate becomes less important, and more important if you
are not using a proper designed solid. Fast Twist Rates can also increase stability of even RN
Solids of decent design, hardly anything can increase stability of a more pointy RN FMJ.......

#8 Sectional Density
Sectional Density will ONLY BE A FACTOR with two bullets that are exactly the same in every
other Factor or aspect. Factors #1 and #2 far outweigh Sectional Density in the terminal
performance of Solids. We can take a properly designed 458 caliber 325 gr Solid and far
out penetrate in depth and stability a poorly designed 550 gr 458 caliber bullet....... My son
recently shot a medium sized elephant at 10 yards, perfectly executed side brain shot, with a
350 gr .474 caliber properly designed solid at 2200 fps. This bullet exited the head on the
far side and still may be going for all I know. A 350 gr .474 caliber bullet has a sectional
density of .223, and I personally would choose this little 350 gr bullet over the Woodleigh
500 gr RN FMJ at .4725 (ones I have here) any and every day for any mission............

These are undeniable facts, and can be proven over and over and over again in all test work,
and these factors have been exercised in the field and have proven themselves in the field,
many many times over...... These are the 8 Factors of Terminal Penetration of Solid
Bullets.................

There it is right there



The guy that wrote that has done more extensive testing in media and on large and dangerous game than anyone ever has.

Of course SD doesn't "take into account" all the other factors. It IS but ONE factor. You posted the definition but do you really know what it means? SD quantifies the bullet's weight relative to its diameter. It is not a measure of lethality like TKO.

For a proper and meaningful test, to determine the role of SD, one would have to drive two identical bullets, differing only in weight at the same velocity. That's how scientific testing works. Change one variable at a time. Your post suggests changing two variables and that would completely nullify the results because you'd have no way of determining which variable effected the outcome and how. Velocity variations have nothing to do with the role of SD. Testing the role velocity plays would involve testing the same bullet at varying speeds. Personally, I think bullet weight and therefore SD has a more dramatic effect on penetration than velocity. We shall see.

But will a 200gr bullet penetrate as well as an identical 300gr at the same velocity???

According to Michael and everyone else you guys have quoted, it will not. So weight and therefore SD, matters. Else we'd use aluminum bullets and get the same result.

The real question is how much does it matter? How much does velocity matter? At what point do they intersect?

I doubt it, but why would you run the light bullet to the same velocity?

I doubt it, but why would you run the light bullet to the same velocity?

Yessir, and im a fan of limiting variables in the lab but it is often pointless if those are never the set of variables seen in real life. At the end of the day i would imagine one can make a bullet penetrate further shooting it out of a gun than just throwing it so i would imagine velocity matters.

Well, it's the only way to determine the effect of each factor, to do so separately. Anybody can say, "this works, let's go kill something with it".

This is how we figure out what works, what works best and why. This is how progress is made. If we don't have answers to all these questions, there is obviously more still to learn. More information is always better. How can we provide a logical argument for this stuff if we don't have all the answers?