KTW 9 x 19 mm green Teflon

I found this picture, but I don’t know if it is a blank version or a special version in synth

It is a KTW armour-piercing (bronze or steel) bullet with a Teflon coating.

this type of cartridge it is use or just a prototype?
someone have data about this cartridge ?

When the KTW ammunition was first put on the market in the late 1960’s, anyone could purchase it. But, it soon become known as “cop killer ammo” as they would easily penetrate bullet proof vests. This was unwarranted as, according to the FBI, no police had ever been killed by anyone using this ammunition. But, because of the misconception, it was soon available only to the police. It was removed from the market in the 1990’s.

The bullets were at first made from a type of bronze called Kennertium (non-magnetic) covered with green Teflon. Later they changed to steel (magnetic) covered with Teflon as it worked just as good and was much less expensive to make.

The KTW stands for Kopsch, Turcus and Ward, the three inventors of the bullet. The early rounds were headstamped “KTW” but later production used mostly Winchester cases, but can also be found in Remington, Smith & Wesson and other cases.

It was made in all major handgun calibers from .25 Auto to .45 ACP.

This is the late bullet ogive and should be the brass alloy bullet with a green teflon coating. It was a production round sold in the US. It must have been out of production 15+ years ago.

I don’t have any performance data, but it was intended as a police load to stop car’s and similar uses. It was introduced long before people were thinking seriously about vests except in the military. The first KTW loads were introduced in the 1967/1968 timeframe.



Some additional information on KTW. While Lew is probably correct that the KTW Round came out in 1968, development began in 1966 and the ammunition was tested by H.P. White Laboratory Octiber 18, 1967. The metal alloy of the first rounds was Kennertium W-10 produced by Kennametal Co., Latrobe, Pennsylvania. The Teflon coating was from Dupont, and the original bullet was covered by U.S. Patent Application Number 679,391. KTW was granted U.S. Patents 3553804 and 3580178. The early bullets evidently had a copper gas check or 1/4 jacket applied, hidden in the case - that is, not visible on a loaded cartridge - which was to engage the rifling upon firing. Around 1971, due to cost (attributed by some writers, but the NRA in a February 1989 article in the :American Rifleman" said that supplies of Kennertium were becoming erratic in the early 1970s, and that’s why the change was actually made), bullets were made by machining plain steel, and finally, the bullets were made of brass. The brass bullets have been talked of as if they were some sort of special brass alloy. However, I had a friend at a Government Laboratory spectrograph one of the .45 bullets for me. Results showed much copper, some zinc, and a trace of MgPbCa; in short, spectrographic results showed the bullet to be plain brass, not berylliium bronze of even bronze.

The early loads with the Kennertium bullets evidently had an admonition on the box not to shoot them in Polygonal twist barrels, as the bullets would not conform to the reshaping process that happens with conventional bullets in these barrels. None of the boxes in my collection, all I am allowed to have representing this type of ammunition in California, have this warning.

Regarding when the change from Kennertium to steel and “other non-ferrous alloys” (brass) took place, a “GUNS” magazine article of September 1973 credits the dropping of Kennertium bullets to two years previous to the article (1971), and alludes to the non-ferrous alloy bullets, so it seems that the brass bullet was introduced no later than September 1973, unless some non-ferrous bullet that I don’t know about was made between the machined steel one and the brass ones.

The articles about this ammunition were very short on ballistical data. One article showed a 9mm 100 grain bullet at 18.000 psi and 1350 fps velocity. Bullet weight is often given as 105 grains for the KTW round, but with no explanation of which bullet is represented by that weight. I have heard that the first bullets of Kennertium were 115 grains, but am not sure that is true. I have boxes showing 106 grains - yes, 106 grains, not a typo, and also for 100 grains, which is probably the brass bullet. I cannot check this as due to my anger at having to give up a major portion of my cartridge collection some years ago, due to California law, I was remiss in making any detailed notes when I removed even my box specimens from the boxes they were in, so have no record of what was in each box.

The Teflon bullet was not there to help penetrate bullet-proof vests, as the ignorant popular press reported (even some gun magazines parroted this nonsense). Dr. Kopsch, the “K” in “KTW” testified that the Teflon coating actually reduced the penetration in Kevlar, and is only there to reduce the likelihood of ricochets.

Of course, there were many other calibers made in this KTW ammunition, than 9mm, but that is another story for another time.

thanks for your explain.


I am sorry to interfere in this topic, but I had the luck to meet Dr Paul Kopsch in Paris, were he was for a touristic trip in 1972, and to ask him some questions, as I had got in touch with him for infos about his rounds…At this time, to carry cartridges by air in your bag or pockets in a foreign country was not yet as intricate as to run an African Safari, so he gave me a collection of specimens of his productions in diverse calibres, together with technical infos. (He had only holed and emptied the case, which were, at this time without any KTW headstamp, only the commercial ones).

The first ones they made were .38 S&W Spl, with unplated brass casez, only after a short run, they began to have them plated. With this calibre, he gave me .357"Mag, 9 mm Para, .30 M1 US Carbine, .32 Auto and .380 Auto, , .38 Super-Auto, Also , curiously in .35 Rem and .350 Rem Magnum.

The 45 ACP was not ready yet (with black Teflon coat, not green). The shape of this bullets was diverse, sharp ogival (regular), ogival truncated, ogival wiith double conicity, truncated…

But the most important thing is that the “famous” KENNERTIUM W10" alloy had nothing to see with any kind of “bronze”, as it was a kind of sintered tungsten powder, with a hot process to form it thanks to a a mix of copper powder bonder.
Paul KOPSCH told me that they had also tried tungsten carbide cores, but that they were extremely costly and to brittle, azs they exploded when impact was over a certain angle actually. They also had to put a copper half jacket in their lower part (not a plain gas check) in order to engage properly the bullett in the rifling.

Well, as usual, I typed a wrong damned key (!) and the post went away before I finished my text!!!

Sorry, here I come again: I found back this details as I wrote an article about it in a French Weapons magazine.

Paul Kopsch also told me that the idea behind the Teflon caoating was:

-first to avoid a too intimate contact between the barrel rifling and the bullet surface, which could destroy it promptly due to the hardness of the projectile material,

-second to better the penetration ability of the bullet in a hard target, like a car motor, thanks to a self-lubricating effect…

The purpose of this KTW was to be able to perforate the door of a car, or the bonnet, then to break in the motor since Turcus and Ward (the two other inventors, from the Lorain local police) had been unable to stop such a vehicle after a bank robbery in 1967.

In their idea, the KTW rounds should have been reserved exclusively to Law Enforcement, and absolutely not for commercial use, Kopsch stated also that precision, with the .38 S&W SPL bullet was excellent in the 25-30 m range, but no more,this making no problem as it was the most common distance for a Police intervention.

Now, last but not least : Paul Kopsch being a shooter, …and a cartridge collector,(!) he had the idea to offer to his fellow cartridge fans an array of KTW “factory dummies”, inert of course and identified by a black varnished base!


I also met Paul Kopsch. I was a 1st Lt stationed in Dayton Ohio and attended the OGCA shows in Columbus. At one of my early shows (late 1967 probably or perhaps early 1968) there was a table near the entrance with a series of metal plates (probalby 1/16 to 1/8 inch thick) welded about 2 inches apart to metal rods so that the whole set was about 3 or 4 ft long. A KTW bullet had been fired into the plates and had penetrated most of them with the bullet still stuck in a plate. The table was covered with photos of the penetration of the KTW loads on old cars, and Mr Kopsch was at the table explaining the cartridge to anybody that would listen. As a new 26 year old collector I was keenly interested and hung around the table a bit. The statement that stuck in my mind was Mr Kopsch’s contention that the bullet was designed so that a standard police 38 Special could be fired into the back of a car, penetrate the body and still have enough energy to crack the engine block. I have no idea if that is true or not, but that is what the design was intended to do at that time. Mr Kopsch told me that they were experimenting with lots of bullet shapes, and I asked if I could get from him the various bullets they were working with in 9x19mm. He agreed to send me some rounds and a couple of weeks later I received the three rounds pictured. No question that these were the original KENNERTIUM W10 bullets. He also made it clear that these loads were intended solely for Police use.

I have never encountered the two pointed bullets in 9x19 cases, though they may occur in other calibers. All three bullets are strongly magnetic. All are loaded in Super Vel cases.

The two pointed bullet rounds weigh 165gr oa and the truncated bullet weighs 177gr oa.

Here are three more 9x19 KTWs that I believe are Kennertium W10 bulleted rounds.

From Left to Right

  1. KTW headstamp so this is likely the final design of the Kennertium W10 bullet. 165gr oa
  2. A dummy with a black case head and R-P headstamp 168gr oa
  3. loaded round with a REM-UMC headstamp. 160gr oa

I think 2 & 3 are earlier versions of the Kennertium bullet. All of these bullets are strongly magnetic. Note the different bullet ogives on the three rounds.

These three KTW loads are very interesting. All have the 9 MM 43 headstamp found on ammunition made in Canada for the CIA.

From Left to Right:

  1. This round is very slightly magnetic. No question it takes a magnetic but if you just touch it to a heavy magnetic and pull it away you could miss the magnetism. It is also very heavy at 266gr oa indicating a bullet that must be around 200gr.
  2. A dummy with a unique flat tip bullet. The case head is black and there is a hole in the case. This bullet is significantly more magnetic than #1 above but less magnetic than the previously described loads. 154gr oa.
  3. This bullet maybe very slightly less magnetic than the loads in the previous two postings, but I couldn’t sware to it, just an impression. It is 173gr oa.

I think these loads, or at least the first two, probably are not kennertium bullets but something else as they were searching for alternate materials. I sure would like to hear from anybody who has similar loads or can shed some light on these loads.

These are the late style KTW loads in the collection with the Brass bullet. All three bullets appear identical. The bullets are totally non-magnetic.

Left to Right:

  1. KTW case-169gr oa
  2. W-W case-168gr oa
  3. HI-PER case-166gr oa

I think the differences in weight are likely the difference in the cases and the three bullets are identical.

The W-W case loads showed up right at the end of KTW’s era and were probably loaded after they ran out of KTW cases.

I don’t know of any US military use of KTW cartridges, but long after the company was shut down - in the 1990s, I was told by someone who was knowledgble and working in Navy ordnance that a US Navy Weapons Location near DC had buckets with thousands of KTW bullets. Not loaded rounds, just bullets. I couldn’t get any of these so I have no idea what style bullet these were.

There is an interesting story somewhere on KTW, but we will probably never see it put together!

Lew and Philippe have added greatly to the story of KTW. My only contact was an interview by phone with the wife of Dr. Kopsch last year. He was not feeling well and could not come to the phone and so she talked to me. A remarkable woman, who knew as much about the ammunition as anyone, having helped in its development. Our conversation centered around the .22 Pokey cartridge and is not relevent here, but simply of interest to report her part in all of this.

Comments regarding penetration have made me spend the afternoon rereading my complete file on this ammunition. The comments concerning penetration in metal - specifically auto body metal and windshields, is correct as Philippe reported it. However, the earlier discussion was about penetration in soft body armor. According to a published interview with Dr. Kopsch (NRAction Newsletter, Volume 4, Issue 5, May 1990):

Dr. K stated that the main purpose of the teflon coating helped bullets go through smooth surfaces, like windshields and car doors, especially at oblique angles. The former Army medical officer likened it to the teflon tip of a walking stock. It simply grabs better.

He further stated “Adding a teflon coating to the round added 20% penetration power on metal and glass. Critics kept complaining about teflon’s ability to penetrate body armor. That was nonsense typical of do-gooders. In fact, teflon cut down on the round’s ability to cut through the nylon or kevlar of body armor.”

Again, according to Dr. Kopsch “It’ll defeat the ordinary ballistic nylon or Kevlar vest, but the teflon gives away its purpose and detracts from its ability to penetrate body armor.”

It seems evident that bore protection was not the major concern regarding the application of the teflon finish, and that the projectiles would pentrate soft body armor at least as well, and better if we are to believe Dr. Kopsch, without the teflon coating. It is also clear from all of the remarks recorded from the various inventors that the primary use of the ammunition was, from the start, evisioned as a weapon against criminals in automobiles, and that penetration of soft body armor was not a concern. At the time they came out, the use of soft body armor by police was not as universal as it is today, and few “bad guys” even knew police wore vests. It was the press and a few anti-gun politicians, as well as a principal in a “celebrity range” in Beverly Hills, California, that brought this ammunition to the attention of the anti-gun press, who rushed to make this information public. They did, as the press often does, a great disservice to police officers throughout the country.

Regarding my comments about reduced ricochet hazard, I must retract those for now. I was going by memory, and forgot that those were comments made in conjunction with long discussions by email of KTW ammunition with various other collectors, from years ago. That comment, also attributed to Dr. Kopsch but without reference to source material proving that, were simply contained in a message to me from another collector. It may be perfectly true, but comments attributed to Dr. Kopsch by the Scholarly source cited earlier in this entry talk about better penetration at oblique angles, which would seem to go against the theory that the teflon coating reduced the potential for ricochets. I should have checked my sources with that and mention that it was an unsubstantiated claim made in material within my files. I apologize to all reading this thread for that oversight.

If that isn’t a classic IAA forum thread…I do not know what is !!

The Best !!!

John, I think “someone” and Lew needs to compile a monograph on the subject of KTW rounds.

Jon - I agree completely. It will be a good subject for Phil Regenstreif and Lew Curtis to tackle! I will enjoy reading it when they finish it.

Thanks everyone—I’ve learned a lot! I agree that a monograph is approprate.

To write a monograph on the 9x19 KTW, it would be useful to know what loads are out there. each one adds a bit to the story. I’ve listed 12 loads/headstamp variations. I’d appreciate the Forum Members adding postings which list which of these loads they have (e.g. Pic 2-3 and 4-1) so we can kind of get a profile of what is out in collections. Guys like John and Philippe and Ray probably have variations I don’t have. When we get it done we can send it to Bill Woodin to see if he has other variations which I’m sure he will.

If you have a variation that is not shown, please post it along with the overall weight and anything you know about it.

If you have any other insights on KTW or their 9mm ammunition, please post that also.

If you know others who don’t visit the Forum, but have info or specimens of KTW, email them and ask them to come look over the thread and give their inputs.

If you guys post the information, I will combine it into an article.

Thanks, Lew

I don

Is the .25 ACP KTW load of any practical use? Surely far too low powered to pierce a car body like intended, even with the KTW projectile.