Home Forums Hunting & Shooting Ask The Gunwriters Barrel length...muzzle blast?

I've found that once muzzle velocity is down toward 2600, maybe 2700, the short barrels don't seem nearly so monstrous. On the other hand, those high velocity numbers out of an 18.5" Model 7 can really get the ears ringing even in the field.

OTH, they sure are a joy to carry.

Does anyone else here try to slip in an ear plug on the left side just before shooting?

The thing that I want to know is are the shorter tubes really louder or is it that they place the blast closer to the shooter's ear?

I suppose it could be both,there are lots of published reports of guys measuring the velocity of a given load as they shorten a barrel,but I know of none where anybody attempted to measure noise in DB at the muzzle and at the area of the shotter ears and face.

Does anybody know? Rocky? JB? Anybody?

I had a T/C Contender Carbine, 16" in .223; firing the thing made my head swim. Short barrels hurt you in two ways.

First, when the muzzle is uncorked, the gases are at a higher pressure. As the bullet travels down the barrel, the gases are expanding to ever lower pressures. As the gases expand against the bullet, they are transferring energy -- kinetic -- to the bullet.

Second, the short barrel puts all those uncorked gases closer to your ears. The intensity of a sound pulse falls off with the square of the distance from the source, so even for a given muzzle pressure, the shorter barrel will hurt more.

I don't believe the burning speed of the powder is as important as the weight of the powder. Of course, for a given peak pressure, you use less of a faster burning powder, so there is a correlation to faster powders and quieter reports.

The weight of the powder is important because it determines how much gas is produced. For a given chamber and barrel, the amount of gases produced largely determines the muzzle pressure.

The energy (pressure and temperature) of the gases at muzzle opening is determined by the peak pressure and the expansion ratio. This energy directly affects the muzzle blast, likely in a couple of ways, such as muzzle pressure, re-ignition of gases, etc.

One must also consider the total volume of gases released, and this goes back to the charge weight. All other things being the same (expansion ratio, peak pressure), the more gases the bigger the bang.

Finally, the bore diameter affects not only the expansion ratio (and thus the pressure), but also the frequency spectrum of the report. The human ear finds loud noises of some frequencies more painful (and damaging) than other frequencies.

If you want a minimum noise deer rifle, get a 30" Uberti 73 Winchester in .357 Mag (if they ever make one). The relatively high pressure rating combined with a fantastic expansion ratio and small charge will produce a mild report report released far from your ears. The current 30" .44 WCF might be even milder, its lower peak pressure compensated by the bigger bore's "boom" versus "crack".

Karl

would like to 'bump' Bostons question - does the crown make a difference here?

I can only hazard a guess regarding the effect of the crown: a large crown angle might help direct the gases a bit more forward than just outward, possibly reducing the blast; but what I know about supersonic flow wouldn't fill a page, so this is only idle speculation.

My guess is the recessed and beveled crown acts somewhat in the same manner as a flash suppressor. Muzzle blast, noise and re-ignition flash contribute greatly to perceived recoil, shooter comfort and quick follow up shots.

I had this rifle crowned for a truck gun to eliminate any concern for carrying it resting muzzle down on the usually dirty floor mats. I think I will have the next one done the same way.

I am sure some military work has been done on at least the flash suppressant issues, which are critical to snipers and artillery.

A friend of mine cut a 300WM down to 20" because he'd managed to damage the end of the barrel. That was the loudest rifle ever, its muzzle blast was something to behold. This was 35 years ago, long before ear protection was common. Two shots with this monster and you were saying huh for a week.

Yes.

The expansion ratio of that stumpy .300 Mag was around 5 -- very bad. That 30" .44 WCF from Uberti would be near 40 -- very good. The longer barrel puts the muzzle about 1/3 farther from your ear, so the sound pulse will be diminished to about 1/2, and that 1/2 is compounded on the low muzzle pressure of the long .44.

Long barrels make quiet shotguns, too.
http://www.metrogun.com/index.html

The original .30-30 1894 Winchester and .303 1899 Savage made their reputation as deer rifles with a 26" barrel. That length cut muzzle blast, making them pleasant to shoot, reducing flinch and letting average hunters hit well. In addition the long barrels gave excellent balance for offhand snap shots.

I have owned two rifles with short barrels...never again!

As I have gotten older, I have settled on 24 or 26 inch tubes, depending on contour and caliber.

Weatherby put out their Vanguard Fibreguard a number of years back in a 20" carbine version in 7mm Rem Mag.. (silly concept really)... I only got it via a swap deal....any calibre at the tme would have been fine for me...

But boy does she have blast !!! even with faster powders a huge fireball results...definately clears the bench at the range !! but less noticable out hunting.....but wear plugs !!!

This thread has taken on a life of it's own. Thanks for all the information!

You have confirmed why I really like 22-26" barrels on my rifles.

I had one of those little ported Marlin 16 inch barreled 44 magnums, boy that looked like a handy cute little gun when I bought it! I shot it in the woods without hearing protection, hope the guy that owns it now still likes it.

vigillinus,

I have an 1894 Winchester made in 1898, a .25-35 with a 26" octagon barrel. It is REALLY pleasant to shoot!

I have a 760 Carbine [18.5"] in .308. It's very loud and gives a bit of muzzle flip at the bench as well.

I'm getting a 7600 in 35 Whelen cut back to 20", so carbines can't be that bad overall.

I often hunt with electronic hearing protection, and I often shoot 16" 5.56 rifles and occasionally shorter. There definitely is a trade. When I can I shoot with a suppressor, I find it more convenient than ear muffs. Haven't taken game that way though. I can testify that a Ruger 44 carbine is very quiet shot in the field, and a 17" .308 is very loud and may deafen friends who stand too near the muzzle while shooting at bears. YMMV.

That muzzle flip or jump rather than the muzzle blast is why I tend to like longer barrels. Longer barrels all else being equal just seem to behave nicer under recoil. I had a Contender pistol with both 10 inch and 14 inch barrels in .30-30. The 14 pushed back in a pretty straight line and was fairly pleasant to shoot. The 10 always felt like it was trying to twist up out of my hand and smack me in the head, which I think it came close to doing a few times before I got rid of it.

this is an old topic but worth reviving. Anyone who fools around with rifles long enough learns pretty quick, a short barrel is usually not fun to shoot. It's about the worst thing you can give a youngster to learn to shoot with in a high powered rifle.

I had a replica Winchester 1887 lever shotgun that I intended on hunting deer with, using rifled slugs. It had an 18-1/2" barrel, one of these Norinco jobs. It actually was quite accurate with just a bead front sight up to 75 yards. I removed my earmuffs to fire ONE SHOT just to see how loud it was before deer season. This was a 12 gauge with rifled Wolf slugs. My ear rang and hurt for 4 days after. I cursed for 5 minutes after firing the shot. That ear is still a little muffled to this day, and it's been at least 6 years since I tried that, or longer. I just got rid of that gun.

A lot depends on the cartridge used. The old lever guns had 20" barrels but low intensity 30-30, 32 Spl, 35 Rem cartridges. That I would say would be ok for hunting, and their record speaks for itself.

A good rule of thumb is, if is has a 30-06 case head cartridge family, use 22" minimum barrel length. 24" if you have more open territory, and don't mind carrying around the extra weight. 26" barrel is too long for type of shooting and hunting I do here in the East. I took a Browning A-bolt 7mm Rem Mag w/scope coyote hunting during the winter, in the hills one day. By the end of the day, that gun felt like it weighed 50 lbs. and my right shoulder was sore from carrying it. Using the same gun in the woods deer hunting, felt like carrying around a pogo stick, the barrel was just too long for brush hunting.

When I buy a rifle new or used, I measure the barrel and want a 22" to 24" length barrel, and prefer the 22". 26" is just too long for the terrain and woods where I hunt, and tends to get hung up in brush, or difficult climbing in and out of tree stands with, etc.

I got a really nice Husqvarna lightweight bolt action in a package deal trade, and it weighed only 7.25 lbs. w/sling and scope, in 30-06. These were toted as the "lighweight champs" during the 1950-60's. But it also had a short 20" barrel. I never even fired it, and sold it. Sure I could fire boxes of shells with it at the range with earmuffs on, and the recoil is never that bad with a recoil pad, which it had. But that light weight and short barrel would not be pleasant to actually shoot with when hunting. The muzzle blast to the left ear would be excessive, and the kick unpleasant. If I handloaded it down with fast powder/light bullets say 120-140 grain, with starter loads perhaps that would calm it down some. But I think that approach is a stopgap band aid- if one has to load a cartridge down that far to make it manageable, that tells me what they need is a milder cartridge like a 6mm, 243, 250 Savage, 300 Savage- or a slightly heavier gun with a slightly longer barrel.

The guy I sold the Husky to, will be rebarreling it to 6.5 x 55. He knows the deal.

This same issue recently cropped up with a model 71 Winchester I was looking to maybe buy. If the price was right I'd buy and shoot it, just because I've never owned a 71 before. But the price was just a little high, so I passed. My reasoning to the seller was, where I live the .348 has limited usefulness. IMHO it is too much gun for a whitetail deer, and too much gun to be a useful target gun. To make an analogy, why go target shooting with a 460 Weatherby Magnum.

His answer was basically agreement, he shot the .348 with reduced loads and cast lead bullets. So it really all boils down to common sense. Most times someone is selling a gun, it's for a reason, i.e. they no longer want it. You learn these things as you get older and buy/sell/trade/shoot many different firearms, a picture emerges as to what ones are most useful and enjoyable to shoot, and which ones are not.

Another thing I learned is, the 30-40 Krag with factory or milsurp 220 grain ammo, kicks more than my 30-06 rifles, due to the heavy Krag bullets. After shooting a long 26" barrel sporter Krag I still have, and running 2 boxes of shells through it, I didn't even bother shooting the 1899 Krag carbine I also had- and sold the carbine. The long barrel Krag kicks like hell.