One for the techies

[Jbob]

Ok so Ive been shooting for a few years now over 10 and like to think I understand the workings of a shotgun well enough to consider what chokes to use etc.

I have been told that a longer shotgun barrel will increase the speed of the shot by a rate of 5fps per inch and with added choke this will increase again. Basically I have been told information that has been read in an article online, see link below.

http://www.thefield.co.uk/shooting/guide-shotgun-choke-22358

Now I'm not saying that this is all rubbish, far from it, but for the average shooter is 5fps worth anything or is it just something of nothing considering a bog standard English Sporter cartridge for clays (28grm 7.5 fibre wad) is going at 1350fps anyway? (speed quoted from English Sporter web page). 

My understanding is choke mainly effects the pattern in terms of spread/density, at given range loosely speaking and barrel length will mainly have an effect of the guns handling characteristics.

If Im wrong please feel free to correct me. Also is there reason to consider shot speed if it only increases by 5fps per inch? 

[haynes]

Your cartridges will vary by more than that and you'll never even know. I doubt many of us would notice 100- 200 fps difference. 

[Jbob]

My thought exactly.

My mate who has got all excited by this is sure he notices the difference. Me I think theres is more to worry about than the speed of the cartridge at the end of the day.

[TIGHTCHOKE]

An article by one of my favourite authors!

 

 

 

 

 

NOT!!!!!!!!

[Dougy]

Just shoot it. 

Spend more time shooting and less time reading and till become a better shot. 

[JohnfromUK]

49 minutes ago, haynes said:

Your cartridges will vary by more than that and you'll never even know. I doubt many of us would notice 100- 200 fps difference. 

+1

[Gunman]

1 hour ago, Dougy said:

Just shoot it. 

Spend more time shooting and less time reading and till become a better shot. 

Hear Hear to that .Best advice is to STOP THINKING .As well as reading magazines and listening to people who have spent to much on guns they dont really need and are having to justify the expense to them self's.

[Ultrastu]

I would imagine that the extra inch could add more than 5 fps . (Possibly up to 20 fps or more .) But is that 20 fps worth any thing ? 

 

No not in the slightest .I also agree 200 fps difference wouldnt  be noticed by 

1 you the shooter 

2 the bird .

3 the range 

If any thing the drop in muzzle  speed could equate to better patterns .higher bc of the pellets .leading to more range and higher striking energy .

Possibly. 

Just shoot it 

Edited January 23, 2018 by Ultrastu

[Scully]

Don’t overthink it; just get out there and shoot. 

[TDS]

I have always been led to believe the opposite of the above , i.e the longer the barrel decreases speed ...

I am sure that i have read many times that around 24" barrel length  is optimum for complete powder burn and then shot speed decreases due to friction  of the wad and shot abrading along the barrel walls

Blackpowder does need longer barrels for complete burn of powder

[buze]

4 hours ago, TDS said:

I have always been led to believe the opposite of the above , i.e the longer the barrel decreases speed ...

I am sure that i have read many times that around 24" barrel length  is optimum for complete powder burn and then shot speed decreases due to friction  of the wad and shot abrading along the barrel walls

Blackpowder does need longer barrels for complete burn of powder

That's my instinct as well. Longer barrels, more probability for flyers (more time/distance against walls) so even if the choke eventually 'concentrate' them, the pellets that have been partially crushed on the walls will just fly off disturbing the pattern.

Another instincts tells me that the longer the barrel, the longer the pressure is present in the barrel, some of which will escape via the other side (in the action) instead of continuing to push the pellets via expansion as this theory seems to imply -- unless you have chambers/action so tight to be impractical... Mind you I have no idea how much pressure is wasted 'that way' but since the semi-auto can churn quite a few bits of mechanical parts using it, I assume there's quite a lot there awaiting dispersion.  

Actually I'm making a very good point here (/me dislocate his shoulder slapping himself on the back) -- *this* theory can't really hold for semi autos, as some energy is diverted on purpose at the other end of the barrels... In fact, I would say that the tighter the choke, the more energy is 'wasted' in the action side of the barrels anyway, by simple the good old P=F/S equation.

I don't mind MikBEEEEEEEEEP YarBEEEEEEEEEEEEEEEP for some things, like his gun mount video are a must see, in my opinion. But well you need a pretty fine sifter to sort out the good from the rest ;-)

 

 

[bigman]

1 hour ago, buze said:

That's my instinct as well. Longer barrels, more probability for flyers (more time/distance against walls) so even if the choke eventually 'concentrate' them, the pellets that have been partially crushed on the walls will just fly off disturbing the pattern.

Another instincts tells me that the longer the barrel, the longer the pressure is present in the barrel, some of which will escape via the other side (in the action) instead of continuing to push the pellets via expansion as this theory seems to imply -- unless you have chambers/action so tight to be impractical... Mind you I have no idea how much pressure is wasted 'that way' but since the semi-auto can churn quite a few bits of mechanical parts using it, I assume there's quite a lot there awaiting dispersion.  

Actually I'm making a very good point here (/me dislocate his shoulder slapping himself on the back) -- *this* theory can't really hold for semi autos, as some energy is diverted on purpose at the other end of the barrels... In fact, I would say that the tighter the choke, the more energy is 'wasted' in the action side of the barrels anyway, by simple the good old P=F/S equation.

I don't mind MikBEEEEEEEEEP YarBEEEEEEEEEEEEEEEP for some things, like his gun mount video are a must see, in my opinion. But well you need a pretty fine sifter to sort out the good from the rest ;-)

 

 

What a load of drivel

 

[Mr.C]

And I thought we were all going to play nice.. 

A counter argument outlining where you think the above theory is incorrect would have been constructive 

The 1st paragraph I can see, the rest I'm yet to be convinced of. 

Edited January 24, 2018 by Mr.C
Spelling

[TIGHTCHOKE]

Thank you Professor Buze, as said above the first paragraph has some credibility, the rest is groundless.

Modern cartridges do their work in the first 10 inches of the barrel, the wad obturates and the case expands, sealing both ends of the expanding gases.

A semi-Auto uses the redundant gases to push on the piston to extract and reload after the powder has done its job.

[buze]

5 hours ago, bigman said:

What a load of drivel

 

You managed 5 words in one single go, WELL DONE bigman. I assume you can't type more because of bigfingers?

[buze]

29 minutes ago, TIGHTCHOKE said:

Thank you Professor Buze, as said above the first paragraph has some credibility, the rest is groundless.

Modern cartridges do their work in the first 10 inches of the barrel, the wad obturates and the case expands, sealing both ends of the expanding gases.

A semi-Auto uses the redundant gases to push on the piston to extract and reload after the powder has done its job.

"redundant gas" would push forward if it wasn't used backward. There's no such thing as redundant gas. Perhaps the loss is 'insignificant' compared to the total velocity, but you can't claim it 'groundless' -- especially when the original discussion is about a very edge effect of 5fps

And if the cases expanded enough to be a full block, you'd have problems removing the cartridge afterward, so there MUST be a loss there.

Also, more generally I hoped we could have a fun argument here, you know, pull interesting whacky theories together, before the usual PW brigade arrived.

[Zapp]

You could always start another topic for fun theories, nobody could complain then.

I get the impression the OP was looking for more fact/experience-based answers.

[JohnfromUK]

18 hours ago, Jbob said:

Now I'm not saying that this is all rubbish, far from it, but for the average shooter is 5fps worth anything or is it just something of nothing considering a bog standard English Sporter cartridge for clays (28grm 7.5 fibre wad) is going at 1350fps anyway? (speed quoted from English Sporter web page). 

My understanding is choke mainly effects the pattern in terms of spread/density, at given range loosely speaking and barrel length will mainly have an effect of the guns handling characteristics.

My answers:

The velocity difference is trivial - and will be lost 'in the noise' of other variations (different cartridges, wads etc used).  It would make no significant difference 'at the target'.

Choke is (as you say) about pattern, more choke = tighter pattern.  Again, there is a lot of difference between cartridges, wad types etc.

Long barrels are (again as you say) about handling, with weight and balance also to be considered.

So - to summarise - you were pretty much right in your opening post - and don't worry about tiny velocity differences, just go out and practice/enjoy!

[Guest cookoff013]

here is my tuppenth.

whats printed on a box is half truth. the speeds often quoted are derived from a pressure test barrel, and often are the fastest of a subset. the test barrel is 28" long.

the same shells run in your chamber (cip chambers are very tight, with very tight tollerences) and your length of barrel will be different, than published on the box.

forget those miniscule changes in speed. its nonsence, its a typhoon in a thimble. letalone a storm in a teacup.

as for choke, with the different cartridges and barrel lengths, all respond differently to choke. some shells work well, others dont, its try it and see. sometimes just going up or down a choke size can kill a pattern, it just goes.

my advice for you if you want to improve game shooting, buy high quality 1300fps shells or thereabouts, maybe larger payloads or larger shotsize, then pattern them, pattern 6s too if quarry distance is close. ir flushing birds / decoy etc. try different chokes, pattern them what is written on the side of the choke does not matter, sometimes full chokes only get 1/4 patterns and vice versa. 

for clays, i ended up going full / full, but i will open that up to 3/4of need be, its because i tend to use small shotsizes (9 for almost everything clay based).

[Jbob]

39 minutes ago, JohnfromUK said:

My answers:

The velocity difference is trivial - and will be lost 'in the noise' of other variations (different cartridges, wads etc used).  It would make no significant difference 'at the target'.

Choke is (as you say) about pattern, more choke = tighter pattern.  Again, there is a lot of difference between cartridges, wad types etc.

Long barrels are (again as you say) about handling, with weight and balance also to be considered.

So - to summarise - you were pretty much right in your opening post - and don't worry about tiny velocity differences, just go out and practice/enjoy!

This was my feeling before I wrote the post, always nice to hear people confirm this though. Seams I have learnt a bit in the 10 or so years Ive shooting.

 

My personal feeling is echoed several times above in that 5fps per inch is trivial even to the point that TDS makes that a decrease in speed could be expected from friction. Does a rifle bullet slow down in a long barrel from friction?

I understand completely that different cartridges react to different barrels and chokes differently, I think I have found my clay cartridge of choice theses days and ignore people who say I should be trying x cartridge because it does this and that. Game wise I don't do so much of that theses days.

It seams some people read a lot and believe what they read and its very easy to drill down to much into the technical side of things. Just go and shoot is my opinion too, you'll learn more about your gun outside in the fresh air than you will reading all evening. 

 

Thanks for all the replies folks hope this thread keeps going so I can read more peoples opinions and hopefully learn more.

[JohnfromUK]

Well, magazines have to sell copies .......... and little really changes on shotguns - barrel lengths go through fashions, new models come that have some claimed advantages ....... but these are minor - and guns made 140/150 years ago still shoot pretty well even by today's standards.

I use 21g (no 7 or thereabouts) cartridges for clays - because they are cheap, nice in light guns, and break clays very adequately for me.  I use 26 or 28g (no 5 or 6) for game which works well for what I do.  I use fibre wads because the ground owners prefer that.  My guns (with one exception) have fixed chokes, most a mix of IC, 1/4 and 1/2.  My multi-choke gun has a box full of the things (original owner ordered a large set) - and I have never changed them.  I think the ones in it are 1/4 and 1/4, but not sure without taking them out and looking!

Whilst I like to read and understand about the 'science', I miss FAR FAR more through my errors than any contribution from velocity, choke, shot size etc.

Edited January 24, 2018 by JohnfromUK

[Ultrastu]

I love those last three lines. 

[JohnfromUK]

13 minutes ago, Ultrastu said:

I love those last three lines. 

Actually - it's worse than that! 

I even bought (from Teagues) one additional choke tube as one was missing (told it had been damaged - and they are very thin) when I bought the gun - and I have never used it.  I do however remove and clean them when I use the gun (which is rarely), so I do know they aren't stuck in.

[bigman]

3 hours ago, buze said:

You managed 5 words in one single go, WELL DONE bigman. I assume you can't type more because of bigfingers?

Ain't I a clever boy 

[Fil]

12 hours ago, bigman said:

What a load of drivel

 

+1