Thread: Short fatties vs long slender ones...

Originally Posted by Hermitage

Yeah PPC inspired designs (short n fat), are indeed more accurate than longer cases holding similar amounts of powder due to less velocity spread (SD over Chrono). But it generally takes a very accurate rifle to prove it out and the short fatties give no increase in velocity over long and slender.

or longer ranges (much longer) where velocity spread has a bigger effect.

Originally Posted by veitnamcam

I thought the short and fat is where its at was more to do with consistant powder ignition/burn for better accuracy?

Pretty much every modern popular chambering for competition shooting has this design.

Yep, and drag out the theories on gas turbulence and try and understand them. Although shoulder design probably has more influence here.
And then there is brass flow to theorise on as well.

So velocity only may be a one dimensional answer.

The original question re barrel length probably wasn't answered.
Nope, I don't have the answer.

Originally Posted by veitnamcam

I thought the short and fat is where its at was more to do with consistant powder ignition/burn for better accuracy?

Pretty much every modern popular chambering for competition shooting has this design.

No sure why the writer of the article chose 300 H & H except of course for comparable capacity with the WSM.
THE 300 H & H certainly meets the long and thin criteria but it's design was such to allow early days loading of cordite strands.

Originally Posted by zimmer

No sure why the writer of the article chose 300 H & H except of course for comparable capacity with the WSM.
THE 300 H & H certainly meets the long and thin criteria but it's design was such to allow early days loading of cordite strands.

I'm picking he had impeccable taste and a yearning for simpler times

Originally Posted by Pushover

I'm picking he had impeccable taste and a yearning for simpler times

Ah, I get it, the good Olde days and nostalgia (usually cockeyed due to brain fade).

I thought it was supposed to be a clinical comparison not an old versus new theme.

so the good old 22hp savage rimmed cartridge would be awesome in a single break open if given a fast twist 224 barrel it wouldnt be giving buggerall away to the modern flash cartridges with similar case size...and be heaps easier to extract....
one day when win lotto....reminds me must get around to buying a ticket one day LOL

Out of pure interest i just ran a 20 inch barreled 7SAUM against a 20 inch barreled 280AI in quickload with capacities being averaged to the same 73Grains and seating depths of the 180 eld m to the same depth to keep useable capacity identical. The results where all the same powders and same loads to reach identical pressures however interestingly the Saum alway leads in velocity at that pressure by 19-20fps. Im guessing this if due to the extra half inch of effective barrel length.
Obviously this isn't a real test but its based on a program based on lots of testing.

The issues (not to discredit it but maybe why they cant be taken as gospel) I see with the 300wsm vs 300H&H test are as follows:
-There is higher case capacity (a few grains) on the 300H&H.
-We dont know what seating depths were and whether they where kept consistent.
- How was the extra barrel added?
- Without seeing the test there appear to be quite a few uncontrolled variables including how to determine actual pressures etc as by feel isn't accurate at all.

I feel there may be an advantage by shorter cases but i imagine its minimal. The consistency of burn leading to a more efficient burn appears to be true so wouldn't a more efficient burn lead to more velocity? Also your half inch shorter the second you drop to a short action anyway so could run a half inch longer barrel for same overall length.

I dont think we will ever see a proper answer but velocity probably shouldn't be the only factor.

Originally Posted by Stocky

Out of pure interest i just ran a 20 inch barreled 7SAUM against a 20 inch barreled 280AI in quickload with capacities being averaged to the same 73Grains and seating depths of the 180 eld m to the same depth to keep useable capacity identical. The results where all the same powders and same loads to reach identical pressures however interestingly the Saum alway leads in velocity at that pressure by 19-20fps. Im guessing this if due to the extra half inch of effective barrel length.
Obviously this isn't a real test but its based on a program based on lots of testing.

The issues (not to discredit it but maybe why they cant be taken as gospel) I see with the 300wsm vs 300H&H test are as follows:
-There is higher case capacity (a few grains) on the 300H&H.
-We dont know what seating depths were and whether they where kept consistent.
- How was the extra barrel added?
- Without seeing the test there appear to be quite a few uncontrolled variables including how to determine actual pressures etc as by feel isn't accurate at all.

I feel there may be an advantage by shorter cases but i imagine its minimal. The consistency of burn leading to a more efficient burn appears to be true so wouldn't a more efficient burn lead to more velocity? Also your half inch shorter the second you drop to a short action anyway so could run a half inch longer barrel for same overall length.

I dont think we will ever see a proper answer but velocity probably shouldn't be the only factor.

Yes most people dont realise that for the exact same barrel length a saum or wsm type cartridge will have a greater length of rifling compared to a longer case such a a 7RM etc.

This has to give a slight increase in velocity for the powder burnt.

Originally Posted by GWH

Yes most people dont realise that for the exact same barrel length a saum or wsm type cartridge will have a greater length of rifling compared to a longer case such a a 7RM etc.

This has to give a slight increase in velocity for the powder burnt.

John Barsness calls the 7mm RSAUM a .280 double improved due to its identical capacity and ballistics. Just don't try and convince a .280 AI fan on this though and especially don't mention a superiority due to the shorter and fatter case.
Grandpamac.

Originally Posted by Micky Duck

so the good old 22hp savage rimmed cartridge would be awesome in a single break open if given a fast twist 224 barrel it wouldnt be giving buggerall away to the modern flash cartridges with similar case size...and be heaps easier to extract....
one day when win lotto....reminds me must get around to buying a ticket one day LOL

Yes Micky quite true. The continentals have been turning out break open rifles in 5.6 x 52R for about a century. They use them for shooting Roe Deer. 5.6 x 52R is just their name for the .22 Savage High Power. Wish I had one too.
Regards Grandpamac.
PS I think that Bergara makes a .223 which should give the same performance but no retro cred.

I was recently offered a .300WM as a replacement for my .300WSM after comparing the ballistics there was a very minor difference between the two across velocity etc.
So stuck with the wsm.

Sent from my SM-A505GN using Tapatalk

mmmm 300 H+H
The 308 P14 rechamber project would be a classic in one of these but a Norma/300 win mag probably easier

Originally Posted by csmiffy

mmmm 300 H+H
The 308 P14 rechamber project would be a classic in one of these but a Norma/300 win mag probably easier

Greetings Csmiffy,
A friend lusted after a .300 H&H Mag years ago. Unfortunately no one seemed to have a reamer and he had to settle for a .308 Norma Mag. It had a 1 in 14 inch twist barrel and shot the 130 grain projectiles at a speed I probably should not mention.
Regards Grandpamac.

Ive thought for awhile now there is LIMITED niche for clever person with lathe to make barrel extensions out of something light,like alloy...say 10" with internal hole of say 10mm and bit threaded to fit barrel with maybe 2" over barrel...so the guy who has chopped barrel to say 16" wants to do tops trip but dont want to carry suppressor...for whatever reason...or going to use mild loads for plinking.....the longer barrel will take muzzle blast away from shooter by enough to make big difference to sound...may even allow more of burn to happen pre new muzzle.....
not a lot more silly than running suppressor and muzzle brake on same rifle....

Greetings Micky,
While we are waiting for our Lotto winnings to arrive I thought I would do some research. Krieghoff offers something that might suit. The Hubertus model single shot looks nice, only 6.5 pounds and only $US 7,500.00. Should I order two just in case.
Grandpamac.