Chamber lengths and recoil

[hp01mp]

Sorry if this has been discussed before. Have looked back through previous threads but can't find anything.

 

Just wondering whether anyone can explain what difference (if any) there will be in recoil between 65/67/70mm cartridges. It's clear that more powerful cartridges are generally longer, but I'm not sure if that's because they contain more shot or more powder, and whether cartridge/chamber fit influences recoil. I shoot an O/U with 70mm chambers.

 

My reason for asking is that I'm trying to select the best cartridge to use following a neck injury, so want to understand all the variables.

 

Most likely I will go with Eley Grand Prix (67mm) or Hull Imperial Game both in 28/6 or 30/5 combo depending on early or late season. I used Eley GP for years but gave up with them following repeated quality issues. However their winning awards for their cartridges again so perhaps they've turned things around? I've had less experience with Hull Imperial Game but have heard they're very smooth. Just not sure whether they'll be less effective than Eley GP because of their length.

 

Thanks

[rbrowning2]

In theory recoil has nothing to do with chamber length.

 

It is all do with the weight of the gun and that famous equation e=m(c*c) i.e mass of the shot multiplied by the muzzle velocity squared.

 

About the only time muzzle velocity is useful.

 

So light gun heavy shot load and high muzzle velocity = lots of recoil.

light gun little shot and slow muzzle velocity = lot less recoil.

Heavy gun then for both recoil will be again less.

 

So just look for a slow (subsonic?) cartridge and minimum shot load effective for your purpose.

 

Rb

[neutron619]

I suggest you take a look at the Eley Hi Flyer range. They have good loads of #5 & #6 without stupid muzzle velocities and I remember being very impressed with how smooth they were when I used them. If I still bought commercial 12 gauge loads, they'd be what I'd choose.

 

Eley Grand Prix are a pretty good cartridge, but I've always found them a little sharp.

 

To address the original question rbrowning is right. All down.to how much at what speed and how much gun (and person) there is to resist it. A 6" cartridge pushing an ounce at 900 fps would still be mild.

[panoma1]

I find Just Cartridges own brand 'xtreme game, fibre, 65mm x 30g x 6's, to be very soft shooting....and they work well in my light English SBS!

[IEH]

I find Express Supreme game in the 28g load very effective and very smooth shooting.

[ditchman]

a lot of "the perceived recoil"...is due to the speed the powder burns at....i generally use nothing else 'cept 2 1/2" carts....but i have used 2 3/4" express carts ..(forgot the brand) they were black...and were 30gm...and they were oh so smooth to shoot....so bigger/longer carts do no equate to more recoil......

 

i have also used Hull 24gm...and they are very sharp in my little sxs............

[SxS]

Worth trying a box of Hull Three Crowns - they're my preferred cartridge in light guns due to lack of recoil. And you get the varnished paper smell!

 

Looking at the Hull website, they also rate them as being softer than the Imperial Game (which I've not shot).

[WelshAndy]

I find Just Cartridges own brand 'xtreme game, fibre, 65mm x 30g x 6's, to be very soft shooting....and they work well in my light English SBS!

My favourite cartridge - shame they are so expensive!

[Guest cookoff013]

a lot of "the perceived recoil"...is due to the speed the powder burns at....i generally use nothing else 'cept 2 1/2" carts....but i have used 2 3/4" express carts ..(forgot the brand) they were black...and were 30gm...and they were oh so smooth to shoot....so bigger/longer carts do no equate to more recoil......

 

i have also used Hull 24gm...and they are very sharp in my little sxs............

Nope- recoil is more to do with speed and weight. The fastest powder is used for subsonic the slowest shells. Sorry ditch you are way off base with this one. You could reload and find out for years self. Those 24g are a different breed international target shell. 1400fps that's faps

[panoma1]

Worth trying a box of Hull Three Crowns - they're my preferred cartridge in light guns due to lack of recoil. And you get the varnished paper smell!

 

Yes I concur.....I used them for years...a very soft shooting hard hitting cartridge!

[ditchman]

Nope- recoil is more to do with speed and weight. The fastest powder is used for subsonic the slowest shells. Sorry ditch you are way off base with this one. You could reload and find out for years self. Those 24g are a different breed international target shell. 1400fps that's faps

 

 

whoops i stand corrected............but surely you need a fast burning powder to push the weight of the shot to get the speed ...hence more kick ?

[motty]

Slow burning ( relatively speaking) powders are used in some very fast steel shot recipes.

[ditchman]

ive opened a can of worms in my brain now.........................i think i will just accept that you pull the trigger ,..and something goes bang...and leave it at that

[Guest cookoff013]

ive opened a can of worms in my brain now.........................i think i will just accept that you pull the trigger ,..and something goes bang...and leave it at that

Yep. I worked out that different shotcharges can extract different energies from the same powdercharge. So it's not exactly predictable per se. However, the powders are made to release energy slower to give lower breech pressures,and higher speeds.

[rbrowning2]

Fast, slow, progressive all over in a few milliseconds they may have significant consequences for the chamber pressure but I seriously doubt us humans can perceive the difference in felt recoil of a variation in fractions of a millisecond. A myth? Nice words that sound good for the cartridge marketing man/woman.

[Rimfireboy]

I normally use eley impax in my sxs 12 and hi flyers in my 20. Both nice carts to shoot imo.

[neutron619]

Fast, slow, progressive all over in a few milliseconds they may have significant consequences for the chamber pressure but I seriously doubt us humans can perceive the difference in felt recoil of a variation in fractions of a millisecond. A myth? Nice words that sound good for the cartridge marketing man/woman.

 

Well - you say that, but the test is easy.

 

For a start, not all cartridges recoil the same, though many use the same combination of wad and shot to give the same muzzle velocity. There was a thread round here a while back about velocities - pick any two next to each other in one of the lists and see if they feel the same.

 

For two, pick a crossover load for a pair of powders, one slow, one fast and load some shells. I don't know about anyone else, but when I shoot 34g of shot using cartridges containing A0, it feels a lot nicer than the same load propelled by A1.

 

The key is that it's the same amount of recoil energy, delivered to the shoulder over a longer or shorter period. A smaller force acting for longer tends to be preferable.

[Old farrier]

Hi gents

 

Think a lot about recoil on guns

Mine is based on having a lot of guns and fireing a lot of cartridges

Firstly if the gun doesn't fit it will kick you more

Secondly if it's bored tight it will kick more

A light gun seems to kick more

 

I know about the equal forces forward and back and all the theories and stuff

Example

Put a 3 inch 36 gram cartridge in a single barrel bakil

Then

Tha same load in a browning waterfowl

 

Hopefully you can get the idea 😊

 

Bought a new browning heritage a number of years ago shot well with the gun but it knocked me about with anything over a ounce load

Anyway bought another one 4 years later double gun day

The newest one was a totally different gun to shoot only different was one being back bored the other not

 

Anyway just my thoughts on this subject

 

All the best

Of

[billy13]

+1 for Hull Three Crowns Paper, i have arthritis in my shoulder and neck from playing rugby and this is the smoothest cartridge ive found

[rbrowning2]

Well - you say that, but the test is easy.

 

For a start, not all cartridges recoil the same, though many use the same combination of wad and shot to give the same muzzle velocity. There was a thread round here a while back about velocities - pick any two next to each other in one of the lists and see if they feel the same.

 

For two, pick a crossover load for a pair of powders, one slow, one fast and load some shells. I don't know about anyone else, but when I shoot 34g of shot using cartridges containing A0, it feels a lot nicer than the same load propelled by A1.

 

The key is that it's the same amount of recoil energy, delivered to the shoulder over a longer or shorter period. A smaller force acting for longer tends to be preferable.

I appreciate what you saying and if you look at the pressure time graph some powder manufacture or proof houses make available then I agree the area under the curve will represent the energy delivered from the propellant. The curves are different for different powders so may be that is what you suggest we perceive. I have little confidence in velocities measured by diy chronograph as the few I have tried including the magnetospeed struggle to give reliable readings for lead shot especially fibre wad cartridges.

I know of no manufacture who actually measure muzzle velocity and it is that which determines the momentum or what we call recoil.

So as with your A1 and A0 loads I wonder if any two identical loads are truly identical in velocity even in the same box of cartridges so if we can feel the difference in a fractions of milliseconds in powder burn rate would not each cartridge feel different due to the small difference in muzzle velocity. It is an interesting aspect of gun ballistics which is personal to each person, some being more sensitive to recoil than others so you may well feel a difference in recoil that I do not, perhaps as simple as how we each mount and hold the gun.