The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

Andy632 wrote:

Sandgroper wrote:A Pascal is measure of pressure and is equal to one Newton* per square metre.

I don't think it should be marked kPa/cm2 as the cm2 is not required because the metric unit (Pascal) already takes area into consideration. It's the same as saying psi per square inch!

BTW, A Pascal is the same as one Atmosphere or 6894.8 psi, so 1200kPA would equal 1200x1000Pa or 1200 000Pa.



*A Newton is a measure of force, but I won't go into any more detail for fear of setting off those metric-phobic amongst us.

BTW, A Pascal is the same as one Atmosphere or 6894.8 psi, ??????????????

You've confused yourself Grant,
one atmosphere = 14.696 psi = 101325Pa or 101.325 kPa = 1.03 Kg/cm2.

Ha Ha! So I did Looked at my old Physics books and read table the wrong way - that'll learn me. :cool2:

I should have written that 1 PSI is equal to 6894.8 pascals or 1 Atmosphere.


I did wonder if they meant to put kg/cm2. My calculations and double checking with a converter came to 17068 psi or 7.6 tons per square inch. I don't know what levels shotgun barrels should be proofed at - does this seem low or about right?

BTW 1200kPa = 174.045psi (double checked before posting! )

In line with Sandgroper's latest:

1 kPa = 0.14504 psi

so 1200 kPa = 174.048 psi but that looks rather low.


A gun will be proofed at say 3 Tons per sq inch ... which converts to around 46,000 kPA

or 850 Bar is 85,000 kPa

So the original 1200 looks rather low.

According to the attached pdf from BASC your barrel has been incorrectly marked. It should be marked in kg/cm2 or bar not kPa/cm2.

It would appear that it should have been marked 1200kg/cm2 which is magnum proofing.

Ok, if the wafflers can stop giving you bad info.

kp/cm² == kilopond/cm² == kg/cm² http://en.wikipedia.org/wiki/Kilogram-force

It is not a (kilo) Pascal or kPa.

1 Bar = 1.019716213 Kilogram-force/Square Centimetre (kg/cm²)
1 kp/cm² = 0.981 Bar

But...
1 kPa = 0.01 Bar

So, using Bar, kg/cm² or kp/cm² you're within 2%, so for the purposes of shotgun proof they're all much of a muchness.

It would be unwise to use a shotgun proofed to 1200 kPa (12 Bar) But that's not any issue for you - modern Lanber's are proofed to 1370 Bar, older guns (pre '89 AFAIK) were proofed to 1200 Bar).

Mikaveli wrote:Ok, if the wafflers can stop giving you bad info.

kp/cm² == kilopond/cm² == kg/cm² http://en.wikipedia.org/wiki/Kilogram-force

It is not a (kilo) Pascal or kPa.

1 Bar = 1.019716213 Kilogram-force/Square Centimetre (kg/cm²)
1 kp/cm² = 0.981 Bar

But...
1 kPa = 0.01 Bar

So, using Bar, kg/cm² or kp/cm² you're within 2%, so for the purposes of shotgun proof they're all much of a muchness.

It would be unwise to use a shotgun proofed to 1200 kPa (12 Bar) But that's not any issue for you - modern Lanber's are proofed to 1370 Bar, older guns (pre '89 AFAIK) were proofed to 1200 Bar).

Thank you. I'd never heard of a kilopond before now, mind you it's not a standard SI unit but I learnt something new.

I do apologise for any confusion caused. I'll go and crawl back under my rock!

shotgun sam wrote:The bottom line will I be able to use 2 3/4 inch magnums? and being a 2006 model will it be steel proofed

2 3/4 inch is a (modern) standard shotgun cartridge. (70mm)

3" is a magnum. (76mm)

If it has been proofed for steel shot, it'll have the fleur-de-lys stamped with the proof mark. I'm not sure the 1200 Bar proof model have that (anyone?).

Sandgroper wrote: Thank you. I'd never heard of a kilopond before now, mind you it's not a standard SI unit but I learnt something new.

I do apologise for any confusion caused. I'll go and crawl back under my rock!

Sorry, I didn't mean to sound harsh. I just saw a myriad of posts talking about measurements in Pascal and thought "Arghhh, that's not it!", so I wanted to get in quickly before people started getting too confused.

Mikaveli wrote:

Sandgroper wrote: Thank you. I'd never heard of a kilopond before now, mind you it's not a standard SI unit but I learnt something new.

I do apologise for any confusion caused. I'll go and crawl back under my rock!

Sorry, I didn't mean to sound harsh. I just saw a myriad of posts talking about measurements in Pascal and thought "Arghhh, that's not it!", so I wanted to get in quickly before people started getting too confused.

I understood that Proof Marks should be recorded in Bar to ensure commonality and reduce confusion. And that is what it did here!

Previously the UK used Tons per sq inch and in Europe Kg per sq cm.

Mikaveli wrote:

Sandgroper wrote: Thank you. I'd never heard of a kilopond before now, mind you it's not a standard SI unit but I learnt something new.

I do apologise for any confusion caused. I'll go and crawl back under my rock!

Sorry, I didn't mean to sound harsh. I just saw a myriad of posts talking about measurements in Pascal and thought "Arghhh, that's not it!", so I wanted to get in quickly before people started getting too confused.

No, not harsh! I don't like giving out duff information and don't mind being corrected if I'm wrong - which I was in this case.

The crawl back under the rock line was more me chastising myself! :lol:

Note to self - Must do better!