EN-19 Vs. Steam-pipe

[rabepobemababe]

I am in the market for a new DBBL, Indian-made, SxS shotgun. Purpose is home-defence (not recreational or competitive shooting). I went through the threads of this forum which were about Indian made shotguns. Having done that, in my consideration are two new guns from different manufacturers in Munger. I saw both the guns, and did not notice much difference in fit, finish or weight. They were actually well made. Firm 'A' is probably the only gun manufacturer from Munger who maintained a website. They claimed on their website that their barrels were of Chrome-Moly steel. Firm 'B' did not have a website. I spoke to both the manufacturers over phone.

Firm 'A' owner, who could speak English, said that their products were the best amongst the ones made in Munger, and their barrels were EN-19. He also said he had ISI (marking from Bureau of Indian Standards, not the Inter Services Intelligence). But he had dealers only in Kanpur, Allahabad, Lucknow and Delhi. If I wanted one of their products, I had to travel to one of these locations along with an NOC from local authorities. When I mentioned Firm 'B' to him, he said, “It is all Raddi”, “Koi comparision hee nahi hai”.

Firm 'B' owner spoke only Hindi, and sounded humble and honest. When I asked him about their barrel material, he said, “Steam pipe se banate hain.” Since I did not understand what he was talking about, he further clarified, “Steam engine me jo pipe istemaal hota hai, wahi hai.” He summed up by saying, “Kharidiye sir. Accha hai. Lasting hai. Sab IOF ka test kiya hua hai.” Firm 'B' had a dealer in Hyderabad. Incidentally, I heard atleast one distinguished member of the A.P. Rifle Association mentioning that Firm B's guns as reliable. One member of this forum too fleetingly mentioned about the “superb barrels” made by Firm 'B' in one of his posts.

Now, I am in a dilemma, whether to travel all the way to Kanpur / Allahabad / Lucknow / Delhi with the botheration of obtaining and carrying an N.O.C. etc., for the EN-19 barrelled gun, or settle for the “steam pipe barrel” gun. Therefore, I was trying to find out what this “steam-pipe” thing is. I read that high-pressure seemless boiler pipes are made to withstand upto 45,000 p.s.i. of pressure, and are indeed high carbon steel. I also read this somewhere:

“The industry standard for 12 guage shotshells is for a maximum average chamber pressure of 11,500 p.s.i. Commercial shotshell ammunition is typically loaded to 7,500 to 10,000 p.s.i. Definitive Proof pressures for 12 guage shotshells are from 19,000 to 20,500 p.s.i.”

If this is true, and if the “steam pipe” barrel is proof-tested by the I.O.F., then it appears that a gun from Firm 'B' should suffice for my requirement. On the other hand, the Firm 'A' fellow held it as "Raddi".

Knowledgeble forum members may kindly advice as to whether it is worth taking the trouble to have a gun with EN-19 barrel, or I should be content with the “steam pipe” barrel gun.

[BowMan]

Hi,

You have posted a particularly interesting question.

Let me first lay down some facts. A Steam Locomotive and develop pressures ranging from 200 - 10,000 psi depending upon design.

This is much lesser than what pressure a shotgun chamber has to face but let me also point out that by the principle of hydraulics when the steam is routed from boiler to a much narrower pipe it will multiply the pressure inside. I need some more time to do the exact maths but let me say I will come back to you on this.

Regarding the EN - 19 vs steam pipe question, let me just say that EN - 19 is simply a classified grade of steel. This classification or grading is done by European Committee of Standardization which is also adopted by BS (British Standards). Now gun barrels are not the only application that this steel is put to. For example it is also used in truck axles and some other such load bearing components in auto industry. It is possible that the steam pipes also use the same grade of steel (EN - 19).

To simplify all this if a gun is tested and certified by a Government than it means it can bear at least 3 times (THRICE) the pressure that it will be subjected to in normal use. Needless to say that it does not really matter if the steel is sourced from A or B. Technically it capable of bearing those pressures.

I hope this helps.

I am not expert by any means so others may also opine on this.

Regards
BowMan

[rajeshsng]

Pressure force is proportional to Area of container. So when steam is bled from a high pressure boiler to low cross sectional area pipe, there will be a chance to decrease the pressure and increase the velocity of steam. So there will be always less stress on the pipe wall than boiler wall plate and hence tube thickness is considerably less than boiler plate

The material used for barrel making throughout the world is EN-19. The manufacturer which use EN-9, EN-19 or any alloy steel for barrel making display prominently by way of permanently engraving on the barrel the type of steel used.
The chemical composition of EN-19 is as follows. 0.37% Carbon, 0.77% Manganese, 0.98% Chromium, 0.21% Molybdenum,uses are axle shafts, crankshafts, connecting rods, gears, high tensile bolts and studs, propeller shafts joints, rifle barrels and breech mechanisms for small arms parts. Due to high tensile strength it is suitable for high pressure applications.

Boiler tubes are high heat resistant, high tensile alloy steels. dont know the suitability of this material for barrels.

[Vineet]

rabepobemababe, instead of writing Firm 'A' and Firm 'B', it would have been better if you wrote the company names. Are you only paying attention towards the material of the barrel? What about other things like ejector/extractor, single/ double triggers etc.

AFAIK sxs guns manufactured by Modern comes with two piece ejectors and are priced around 22K.
There are also sxs guns by P.Fizer that comes with single trigger, priced 26K.

[rabepobemababe]

Avoiding mention of the Firm names was deliberate. I was really curious about this "steam-pipe" thing, and was looking for an objective assessment. Both the guns were of the coach-gun variety, the ones which a lady can swing around with ease indoors in a burglary / dacoity kind of a situation. The "steam-pipe" gun infact looked good and felt good in the hand (balanced well). I could not measure the barrel length, nor the gun's weight. Its barrel was probably 20" or 22", and the weight may be about 3.5 kg. The barrel was meticulously neat inside and outside. It did not have any ejectors, nor single-trigger, but then I was following the K.I.S.S. principle ("Keep It Simple Stupid"). There was nice engraving on the stock. The only thing I did not like about this gun was that they used gold-coloured paint to put the firm's logo and the wording, "King of Guns," at the bottom of the grip. The paint looked as if it is likely to peel off after sometime, and make the gun look shabby unless repolishing of the wood is done. I am not aware of any dealers of Modern or P.Fizer in Hyderabad. If you are aware of any, kindly do let me know. I have PM-ed the names of Firm-'A' and Firm-'B' to you.

[BowMan]

Well objectively, the firm A which says it is using EN - 19 could be using something else and firm B claiming is is using steam pipes may be (unknowingly) using good quality EN - 19.

The person who can be most objective about this is you yourself as you are in best position to evaluate both products by inspecting them closely. As some members pointed out there are other components also which should not escape your attention.

To me it is not reasonable to rule out the firm which says it uses 'steam pipes' just because of that. A bit of travel is always involved when it comes to weapon hunting.

Do post pictures of both products if possible as this can be interesting.

[rabepobemababe]

Well objectively, the firm A which says it is using EN - 19 could be using something else

That's how the distinguished A.P.R.A. member-friend dismissed the claim of EN-19 barrels on Firm A's guns when I mentioned about it to him.

[hks2056]

Steel needed for rifle and shotgun barrel are totally different. Shotgun barrels, being thinner, need milder steel. No Indian shotgun maker uses any grade higher than EN9. Most use EN7. IOF shotguns were made of EN9 steel . EN 18, EN19 and EN 21, which are harder steels, are used for rifle barrels. Any shotgun barrel made of EN18 steel will crack on firing as it is hard steel. Quality of Indian made alloy steels is suspect. I know the owner { IIT Engineer} of a reputed Tool Shop in NCR who supply parts for high pressure and high stress work. He told me that Boehler D2 steel is thrice as hard as any Indian made D2 steel because for making the identical machine component the Boehler alloy blunts three drilling tool bits in comparison to just one tool bit required to work an Indian made D2 alloy. Any one claiming to make EN19 Shotgun barrel in India is a pure rip off. In all probability the so called EN18 is actually nothing more than EN7 or EN9.

[rabepobemababe]

@hks2056,

That's quite a contrarian view, especially when everybody seems to be going gaga over EN-19 & EN-24 barrels for their shotguns. I knew though, of incidents (outside the domain of fire-arms) where the actual quality of steel imported turned out to be less than what its specifications claimed. It seems this happens a lot with the Chinese steel.

So, does it mean that irrespective of who states what, IOF proof-testing alone is the final barometer for the technical soundness of a shotgun's barrel, and that we should ignore even the "prominent engraving" of EN-19 on an Indian shotgun barrel?

Also, I notice that EN-7 is the carbon steel used for wheel-sets of railway coaches built in India. Its composition according to the BS-970 specification is: Iron with - Carbon 0.1%-0.3%, Manganese 1%-1.3%, 0.25 (M) Silicon, and trace amounts of Phosphorus and Sulphur impurities. It has no Chromium or Molybdenum, and therefore cannot be called as Chrome-Moly Steel. Thus, a manufacturer using EN-7 for his shotgun barrels, cannot boast of Chrome-Moly Steel barrels.

The boilers and steam-pipes of the steam-locomotives used in India on the other hand (both pre-WWII and post-WWII), were stated to be DIN ST34 carbon-steel. This steel too, seems to be having no Chromium or Molybdenum. It is composed of Iron with 0.18% Carbon, 0.4% or more of Manganese, 0.35 (M) Silicon, and trace amounts of Phosphorus and Sulphur impurities. I was checking up the mechanical properties of this steel. According to a Czech steel company's documentation I could lay my hands upon, the DIN ST34-2 carbon steel that they supply, has the minimum yield point at 240 Mega Pascals (34,809 p.s.i.), and its breaking strength (tensile strength?) at 400 Mega Pascals (58,015 p.s.i.). I don't know if this is the standard for all the DIN ST34 carbon steels.

If either of these steels can withstand above 30,000 p.s.i. of pressure, and does not crack, then it would be deemed as suitable for the barrels of shotguns. In that case, the steel from "Railway steam-pipe raddi" seems to be eminently suitable for a shotgun barrel. It is also my guess that the gunsmiths making barrels out ot "Railway steam-pipe raddi," would employ some kind of crude-test to pick out suitable barrel material. They may not be aware of the technical specifications or the grade of steel, but still cannot be expected to be totally ignorant of the strength requirements of a shotgun barrel. What Bowman said in his second post appears to be correct!

In addition, I wonder what percentage of imported shotguns available in India would be having EN-19 "prominently engraved" on the barrels.

[Katana]

Steam pipe? That's a new one!

We need a sticky on shot gun barrel material too. I believe barrels can be procured from a firm in Bombay in case a manufacturer is willing to make the complete gun for you.

[rabepobemababe]

Is this the company:



They seem to be having great machinery!

India makes all types of high quality steel. With such machinery and skilled man-power being locally available, I wonder why do our gunsmiths struggle to make good fire-arms?

They have given their contact numbers on their new website, www.preciholesports.com.

[Katana]

I have seen Mehar Singh shotguns with EN24 stamped on the barrels and action. And they are really light! Just that I have not fired any.

[hks2056]

Dear KATANA
Kindly read the following
http://www.cieng.org/events/lectures%20 ... s%20v1.pdf

The EN24 is very hard steel used for tank armour. For shotguns, which are thin walled, mild alloy steel is needed. Here in India stamping is meaningless unless certified by BIS lab.
Regards

[rabepobemababe]

I was doing some more reading on shotgun barrels. Picked up the following tit-bits (subject to verification and confirmation):

1. The pressures experienced inside a modern shotgun barrel are approximately 1/5th of the pressures experienced inside the barrel of a modern rifle that uses regular ammunition. Therefore, shotguns are more forgiving with respect to the barrel material.

2. A rifle barrel's requirement is for rifling inside that will not wear out for atleast 5,000 rounds. Since a rifle's bore is much smaller compared to, say, a 12 guage shotgun, even in rifles with pencil thin barrels, the wall thickness can be kept relatively high compared to the bore. Both these factors mean that considerations for a rifle barrel are different from that of a shotgun, and such considerations warrant the use of harder alloy steel in rifles than in shotguns.

3. Remington, for one, had manufactured modern shotguns whose barrels were stamped as “de-carbonized steel” and “Remington steel” (not to be confused with the character enacted by Pierce Brosnon). Both the barrels were essentially mild steel coming out of a particular forging process, and were meant for use with the regular ammunition (not nitro). A few of these shotguns are still in use, and some must be in India too. Remington did have another series of shotguns whose barrels were stamped “Ordinance Grade,” meant for use with the nitro ammunition. This steel was different, and was some kind of thicker alloy steel. Remington's documentation for the “Ordinance Grade” shotguns made it clear that these barrels “far exceed” the strength requirements of a regular shotgun barrel.

4. There are umpteen grades of mild steel / carbon steel / Chrome-Moly steel. Some carbon steels / mild steels approach Chrome-Moly steels in strength and vice-versa.

5. AISI 1137 carbon steel is favoured by a few shotgun manufacturers even today, and this is not Chrome-Moly steel.

Incidentally, I found a very good reference book (Jorgensen Steel Reference Book) on different kinds of steel, their properties and specifications, and uses on Scribd.com. There is also an article by Ed Harris on metallurgy of guns, dated 16th March, 2012 here:

http://www.grantcunningham.com/blog_fil ... ruger.html

Though most of the article is about the metallurgy of Ruger's guns (Ruger being Ed Harris' employer), he makes a passing reference to the steel used by other gun manufacturers. Note his remark which says, "Most of the other makers buy standard AISI grades in gun barrel quality, typically 1137 for shotgun...."

As such, I am curious to know what steel Precihole Machine Tools uses for its shotgun barrel blanks. Can some one throw some light?

[sa_ali]

Couldnt resist joining in.

Precihole Machine Tools have being making in roads in Jammu gun manufacturers for long time. Initially they had offered EN-19 barrells, not 100% finished but basic barrel.
Lot of Gun manufacturer have started using the EN-19 barrel supplied, but the machining and finishing it is not easy, hence not all have taken fancy to it. They are making them, but in smaller no, its mainly getting used in the O/U which is being old at more price than SxS.
EN-19, is steel, which is used by lot of O/U manufacturers world over, the main reason for the shift to this from the EN-9 (mild Steel) is it is better steel, it will handle pressure better than EN-9, wear and tear is less than EN-9 as its harder. Other reason which i feel is that now that loads are moving from copper to Steel, you definitely need steel harder than EN-9.
I have not heard of any Shotgun manufacturer using steel more harder than EN-19, which is correctly point out. More harder steel is not good for Shotgun, they are good for rifles, its not a scenario of harder the better .

Now the precihole have used the same in road of supplying barrel to gun maker to making airgun themselves.
http://preciholesports.com/index.html
http://www.indiansforguns.com/viewtopic ... &start=105
See page 8 of this.