Weapon light discussion, (loosely) related topics welcome

kerneldrop

Flashlight Enthusiast
Joined
Apr 24, 2021
Messages
2,333
Location
South
...but wanted to ask if sectional density is still a thing, as it relates to penetration.
And bullet design that addresses complication of passing through other materials first.

Yes, but it's just one ingredient to the recipe.
It sounds humorous, but long-rod penetration theory is the premise of military weaponry designed to penetrate.
That's basically what SD is...the higher the number the longer the bullet, thus in theory the more it will penetrate at a given velocity.
But in comes bullet construction, which is more critical to penetration. And then there's the materials/medium a bullet must pass through.
When comparing the same family of bullets, the SD will give you an idea as to what should penetrate deeper.

Oddly enough, there's a point in speed where the faster the projectile goes the less it penetrates. The reason is because of Newton's Third Law that says you'll receive as much force as you give. Eventually the force is so much that it destroys/deforms the bullet. handguns will never reach that speed....but still neat.

With handguns, makers want to simply control expansion and reach the FBI penetration depth at a certain velocity.

SD within a given velocity is the reason that a certain bullet within the same family within the same cartridge performs better than others.
Just a hypothetical example, many say a 124gr Speer Gold Dot in 9mm out performs the 147gr Speer Gold Dot in 9mm, or vise versa.

In it's simplest form, you need a mix of velocity and mass. One without the other does nothing, and too much of one decreases effectiveness.
Once you solve that ratio, you design a bullet intended for your purposes.
 
Last edited:

IMA SOL MAN

Flashlight Enthusiast
Joined
May 18, 2023
Messages
2,126
Location
The HEART of the USA.
When does it become pointless to up load the cartridge, will you get much benefits from hot loaded .357 if you shooting it from a 2-3 inch barrel?
I used to spend quite a bit of time on the S-W forum, and the consensus there seemed to be that you were better off with shooting .38Spl+P Short Barrel rounds in a snubby (J-frame) than a .357 Magnum, as the extra powder doesn't really give much extra velocity, but a lot of blast, flash and recoil. I tried the Gold Dot short barrel, and it still has a sharp and painful recoil (to me, YMMV). Now I load with target wadcutters, as accuracy is more important, and JHPs don't always expand, anyway. A wadcutter is going to cut a .357 size hole, and not behave like a round nose or plugged, unexpanded JHP. Having said that, the Hornady Critical Defense looks good, and someday I may switch to it. The LeHigh rounds also look promising.
1701633427135.png

Lucky Gunner has great gel videos and expended round photos and dimensions for comparison.
 

SCEMan

Flashlight Enthusiast
Joined
Nov 6, 2005
Messages
1,861
Location
Treasure Valley, Idaho
Now I load with target wadcutters, as accuracy is more important, and JHPs don't always expand, anyway. A wadcutter is going to cut a .357 size hole, and not behave like a round nose or plugged, unexpanded JHP.
Good choice. With 2-2.5" barrels there's not enough velocity to expand HPs and if they did, penetration would not be adequate in most cases.
 

orbital

Flashlight Enthusiast
Joined
Feb 8, 2007
Messages
4,216
Location
WI
+

Watched this while back, the difference in ballistic gel w/ 357sig & 357sig hollow.
spoiler:: big difference

 

KITROBASKIN

Flashlight Enthusiast
Joined
Mar 28, 2013
Messages
5,334
Location
New Mexico, USA
Lehigh Defense:

"The advanced technology Xtreme Defense Fluid Transfer Monolithic (XD FTM) is changing the way self-defense bullets are perceived. Like the Xtreme Penetrator, the progressive nose geometry allows for deep, straight penetration while creating a permanent wound cavity diameter exceeding that of most expanding bullets. Additionally, the bullet is solid copper, able to overcome barriers to penetration, is environmentally friendly and does massive tissue damage on impact. Penetrating barriers such as drywall or heavy clothing prior to impacting the intended target doesn't have the potentially negative effect on the Xtreme Defense that it does to conventional hollow point bullets.

The nose design is the key. The Fluid Transfer's radial flutes force the hydraulic energy inward and then as the energy is restricted, it accelerates outward creating high pressure spikes severely damaging surrounding tissue. This very rapid increase in fluid flow creates cavitation and massive tissue damage away from the projectile equivalent to those of the best hollow points on the market. The result of the Xtreme Defense is a permanent wound cavity that is two to four times greater than what a flat or round nose bullet generates and often larger than traditional or solid copper expanding bullets. What you get is a self-defense bullet that will shoot through barriers without deformation or trajectory change and creates a larger permanent wound cavity coupled with the desired 18 inches of penetration."

 

kerneldrop

Flashlight Enthusiast
Joined
Apr 24, 2021
Messages
2,333
Location
South
Lehigh's rifle bullets are devastating no doubt.
However, small-arms handgun cartridges do not have the velocity required for hydrostatic shock, which is highly controversial any ways even at 3,700 fps.
Lehigh claims the bullet is hard enough to go through barriers yet soft enough to expand in soft tissue. That's a magic bullet.
Monolithic bullets will always be harder and lighter than cup and core bullets. The reason for that is copper is lighter than lead...so it takes a longer copper bullet to hit the same weight as a shorter lead bullet.

To give you a comparison of monolithic bullet designs.....Hammer Monolithic bullets are designed for the petals to break off and tumble while the core continues penetrating. Lehigh is designed for the petals to peel back but not off, resulting in maximum expansion but not as deep penetrating. You can't have both maximum expansion and maximum penetration...it's against physics.

Here is a picture. Hammer on the left, and a Lehigh on right. Two different purposefully bullet designs.
1701651373511.png
 
Last edited:

orbital

Flashlight Enthusiast
Joined
Feb 8, 2007
Messages
4,216
Location
WI
+

My guess is very few weapon lights are owned, even though there were recommendations and even saying not to buy a certain brand, wow.
I got one in '22 ~ Chance is getting one today I think.

Like I mentioned before, mine is on a 10mm Hi-Point carbine, my least expensive firearm,, and the one I'll grab first in home invasion simply because it's easy to shoot & is surprisingly powerful.
 
Last edited:

Hondo

Flashlight Enthusiast
Joined
Oct 26, 2005
Messages
1,544
Location
SE Michigan
I thought this was a thread about weapon lights.
It started when I could not find the weapon light forum any more, and wanted some CPF opinions for my purchase. I changed the title to be more generic, but we have a lot of good topics related to "weapons" in general, so perhaps I will add "...and related discussions".

BTW, my TLR-7A landed, and I have it mounted to the G19, and the fit is, in the words of Ace Ventura: "Like a glove!"

Very happy with the floody beam, and also glad I did not opt for something with more output. It is brighter than almost all of my handheld lights, and having well over an hour of runtime on a single CR123 is awesome.

Now if my local range will open up after renovations, I can really try it out. Sad part is, my range and gun shop lost their FFL, along with half of the other shops around me, so they can't sell guns any more. Seems the AFT (POTUS' spelling, not mine) has trolled all of the shops records looking for clerical errors to use as fodder to get them revoked. It seems the shops are run by human beings, which are imperfect. Who knew? I knew they were targeting individuals selling out of their home, this was a shocker. But props to them for staying open for all services other than firearm sales.
 

Hondo

Flashlight Enthusiast
Joined
Oct 26, 2005
Messages
1,544
Location
SE Michigan
...
Also, it's an actual school. Not just a shooting range. One of the biggest challenges is helping students who were exposed to competitive shooting sports, unlearn certain behaviors. I distinctly recall one student who was told a Spree Shooter was on a crowded public street. He was told to find cover, draw his weapon and return fire if he could safely do so. The issue.... Although he found excellent cover (using an SUV and its engine block to shield himself), he then broke cover trying to get behind a tree that offered considerably less protection. When asked why he did that, he responded that he was trying to get closer for a better shot.
...
I knew what he was doing. He was moving to the next "station."
...
I'm sorry, but I can't agree that participation in Shooting Sports is better than no training at all. It's not like it was decades ago. You don't have to set aside several days of vacation time, fly to Arizona, book months in advance to participate over at Gunsite Ranch, when Jeff Cooper was running it. Pay for your round trip ticket and hotel stay. Thunder Ranch made things a bit easier when it came into existence. But, point is; reputable schools were few and far between. That's just not the case anymore. Those who are serious when it comes to learning defensive use of various types of firearms, no longer have to settle for local Shooting Sports competitions to at least learn something. It's just not the case anymore.
...
Serious students can find schools that deal specifically with self-defense.
...
The ones who are a blank slate and willing to learn, are just easier to teach than the ones with a Shooting Sports background.

I think we are in violent agreement. We are both laying out good examples of muscle memory from training that works against you in the real world. Your perspective (understandably as an instructor) is the tedious task of fixing bad habits ("training scars") once someone seeks defensive training. I still maintain having shot in action pistol events is better than standing in a range booth, or not training at all. When you say it IS worse than no training, your perspective is still that they will, because it is relatively more available these days, seek defensive training. If the do, and they continue to practice what they learn in realistic scenarios, I agree it's best to have that "clean slate". Personally, and unfortunately, most of the people I know who have firearms for personal protection fall into the "range session" only experience. If it is a given that they just won't seek defensive training, then I think we could conclude they would benefit from training that gets them moving, handling the gun from the holster, under pressure from time constraint etc. I know it depends a lot on what sort of competition, who is putting it on and what level of effort is put into "winning the game". But one good aspect of competitive shooting is it tends to get people out and practicing more, even if the events themselves become the practice. When most people "take a class", they may progress to another level or two, but they tend to consider themselves trained and go long periods without using the skills they learned.

Speaking of "muscle memory", I'd like to throw out a scary story from a concealed carry citizen and hear your take on it first:

Our guy drops his GF for a quick errand and waits in the car, not relocking it when she leaves (root problem). A dirt bag, we'll call him DB opens the passenger door and drops in the seat with a handgun pointed at our guy. Our guy manages to unholster his Glock 20 from his hip and points it at DB. This is obviously a SHOOT scenario. Neither one shoots, and DB panics and gets out and is gone. Our guy is obviously amped up, but baffled as to why his gun did not discharge as he thought he was pressing hard enough to almost break his trigger finger. The problem? He instinctively drew his gun with his trigger finger extended along the frame of the pistol, and never moved it inside the trigger guard.

I will share my thoughts a little later.
 

Kestrel

Flashaholic
Joined
Oct 31, 2007
Messages
7,314
Location
Willamette Valley, OR
Other reading for anybody interested:

 
Top