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Discussion Starter #1
Ballistic charts usually give data for .270 win for a 24 inch barrel (i.e. 3060 ft/s at the muzzle for a 130 grian bullet). What average velocity, and trajectory shall I expect for the same commercial loads at different distances shot from a 22 inch barrel?
 

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I haven't shot factory loads in my 270 in about twenty years, but my 22" gets just under 3,000 fps with the load I use. On average, you probably lose 40 - 50 fps per inch between a 22 and 24 inch barrel.
 

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My experience has been that I lose around 20-30fps, per inch of barrel lost, so the same thing Shawn mentioned.

The difference in trajectory is virtually nil and very little, short of shooting at those distances, will tell you what to expect.
 

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If you use a bullet traveling 2500fps and shoot a deer, then the same bullet traveling 3000fps, what will the end result be if both are properly placed?
 

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The Hog Whisperer (Administrator)
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More bloodshot meat with the higher velocity load, assuming the same bullet.
 

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Lyman lists some velocity losses by chambering. A .270 win shooting 130 grain pills will lose 37 fps per inch going from a 24" barrel down to 20".
 

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In Ken Waters' Pet Loads he notes a 100 fps loss going from a 24" to a 22" barrel with same loads in same rifle. He also said Jack O'Connor noticed the same thing. One of my 270s has a 24" barrel and I've noticed it's definately faster.
 

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Waters tested couple rifles of the same chambering. The short barrel was faster than its longer counterpart.
Guess I'd say it depends on the tube.
 

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Waters tested couple rifles of the same chambering. The short barrel was faster than its longer counterpart.
Guess I'd say it depends on the tube.
 

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Discussion Starter #10
Were those tests performed with the former loads throwing .130 grain bullets at 3140 fps?
 

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Hi E.O.

I have 2 .270 Win rifles: a ~45 year-old Model 700 & a Sako AV, both have 22" barrels. With the definitive .270 Win load: W-W brass, CCI 200/Fed 210M primers, 60 grains of H-4831, and 130 grain Sierra GameKings/Nosler Accubonds both of my rifles will chrono at over 3000 FPS. I probably could get higher velocity, but the definitive .270 Win load will shoot .25" @ a hundred all day long. Within reason, I'd rather have accuracy than velocity. This load will drop mule deer & antelope in their tracks.

I've chrono'd 150 grain Partitions at 3000 FPS. I used RL-22 for the load. It's safe in my rifles. It's my .270 Win elk load. However, it ain't as accurate as the aforementioned .270 Win load. Hence, after thinking it over, I'd probably use 130 Accubonds for bull elk. All I gotta do is put one where necessary equipment for topside oxygenated blood for is and I'll have a dead bull...and a lot of work.

The way I see it, accuracy is most important...assuming bullet matches game.
 

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E.O.

BTW, I've read accounts of shooters getting over 3100 FPS using IMR 4350 & RL-19 powders & 130 grain bullets. I have no inclination of trying because the definitive .270 Win load is so darn accurate in my rifles.
 

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Were those tests performed with the former loads throwing .130 grain bullets at 3140 fps?
In that particular instance I'm not sure the test subjects were .270s. But they were shooting the same ammo.
 

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Waters tested couple rifles of the same chambering. The short barrel was faster than its longer counterpart.
Guess I'd say it depends on the tube.
I've read quite a bit of Pet Loads and don't recall him finding a shorter barrel faster in the same chambering. Maybe there is with some I don't remember but speaking specifically of the 270, he found a 100fps gain that was also noted by JOC:






I too found a noticable gain between the three 22" 270s and my 24". I know I was trying to load down my 24" with C & C's as even with mild loads with the 130 GameKing, I was mid 2900's. I can't quanitate the actual difference in FPS, but I think I'll make it a range project this year with the same loads and see what the average is between them.
 

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Interesting, but put the 100fps difference in any ballistics program, and note how little difference there is in point of impact at 300 yards..... probably inside of an inch.

The myth that another 100fps makes anything noticeably 'flatter shooting' has probably sold more new guns, and caused handloaders to wreck more guns, than anything else.
 

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I've read quite a bit of Pet Loads and don't recall him finding a shorter barrel faster in the same chambering. Maybe there is with some I don't remember but speaking specifically of the 270, he found a 100fps gain that was also noted by JOC:
That's pretty much what I based my response upon. My load is nearly identical to that in the second paragraph (130 gr. bullet with 56.5 gr IMR-4831), but I get about 60 fps less in my 22" than Waters got in his. Based my estimate of 40 - 50 fps per inch between a 22" and 24" on these results.

MikeG is correct in that the difference between the two barrel lengths is irrelevant in the field with a hunting rifle. What is significant is the accuracy achieved; Waters' results with the IMR-4831 load parallel mine. I do not echo his sentiment that a barrel shorter than 24 inches is in any way a handicap at ranges which game is shot. I might be concerned if I was competing with a 270 in 1,000 yard matches, but there have been better cartridges for that work for many decades.
 

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Interesting, but put the 100fps difference in any ballistics program, and note how little difference there is in point of impact at 300 yards..... probably inside of an inch.

The myth that another 100fps makes anything noticeably 'flatter shooting' has probably sold more new guns, and caused handloaders to wreck more guns, than anything else.
I agree a million percent.

Don't get me wrong. The 7MM Rem Mag is an excellent cartridge. I own a rifle chambered for the 7MM Rem Mag. It wasn't until I got in to hand loading and read actual scientific data did I come to understand external ballistics and terminal ballistics. Any advantage the 7MM Rem Mag has over the .280 Rem is abstract. Where it counts, hunting big game, the .280 Rem is the 7MM Rem Mag's de facto equal. Hence, were I given a do-over, I'd go with an excellent quality bolt action 22" barreled .280 Rem and never look back. I love accurate, lightweight, fast-handling rifles. Carrying a 10+ pound 7MM Rem Mag up-and-down high ridges of the Rockies ain't fun.

If we were to exclude the legendary penetrative ability of the 175 grain .284 caliber bullets, difference between the .270 Win and .280 Rem is academic.

With age comes wisdom. Knowledgeable hunters who're confident in their abilities and with their rifles seem to be the ones filling tags. I've seen too many hunters bench shooting mega magnums who couldn't print a group were Gutenberg instructing them. They'd have been better served had they bought rifles that didn't knock them into next month.

MikeG is absolutely right. Mega magnum mania was created by marketers and gun writers, the latter being pulp entertainers. If a hunter wants to believe that his .300 RUM is necessary for North American big game, I'm good. He knows what's right for him. He'll cause my synapses to misfire were he to tell me that his .300 RUM will kill deader than an '06 or .308 Win. Big game have no clue what has caused their brains to stop sending signals necessary to sustain life.

Arrows at 300 FPS kill the largest of North American big game every year. But if a hunter believes an extra 100 FPS will fill his tag, I' good. Within reason, I'll take accuracy over velocity. The primary reason I went with a .308 Win in a Featherweight was the .308 Win is an inherently accurate cartridge. To me, the velocity advantage of the '06 was immaterial.
 

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Interesting, but put the 100fps difference in any ballistics program, and note how little difference there is in point of impact at 300 yards..... probably inside of an inch.

The myth that another 100fps makes anything noticeably 'flatter shooting' has probably sold more new guns, and caused handloaders to wreck more guns, than anything else.
No doubt about that. To put it in further perspective, I've thrown rocks through my chrony and got 70 fps. In my younger years or someone with a better arm could probably make it 100 fps. When we're talking a bullet going 3000 fps, Not a whole of difference.

But just as they say speed kills and it also sells. I know I like getting the most out of any round I have and a little extra doesn't hurt esp with something like a TTSX or maybe extended ranges for some.
 

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Barrel length does carry some element of predictability regarding velocity, but barrel length doesn't necessarily limit the typical velocity of a cartridge, there are other internal and external ballistic factors involved.

I've had two identical barrels in which one shot significantly faster / slower than the other when using identical load developments. I have a 22" barrel that won't get above 3000 fps, while the other one will tip the scales at 3100 fps and then some. Some barrels are just faster or slower than others, it's just how it is. That doesn't change the fact that a longer barrel will have a higher velocity potential than a shorter one, but 2" isn't worth considering unless you're a competitive shooter IMHO. In my neck of the woods shots at game are commonly at distances out past 500 yards and beyond. But as long as we know what our rifle does at those distances, it simply doesn't matter to the deer taking one behind the shoulder. Dead is dead, neither the amount of velocity that bleeds off at 500 yards, or the 50-60 fps that's lost at the muzzle matters. My daughter in law killed a couse deer couple years ago at about 560 yards with her .270 Tika Lite with a 22" tube, BTW, those couse deer only weight about 90 or 100 lbs., not a big target. But we've also dropped big bodied mule deer weighing probably 250 lbs. at those distances also. I don't know what down range velocity is, all I know is it's enough to efficiently kill any big game we've shot.

SMOA
 

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I've looked at this for decades. Over the same period I've also owned a chronograph.

It seems that any given barrel length for the same round can vary at least as much as the 50fps-100fps difference usually proposed for the 2" difference in barrel length. I have on rare occasions had a load that hit the same numbers as a manual load. Usually I'm short on speed by at least the amount suggested in the manual, by more than any numbers used for the barrel length. I currently have four .223's with 16" barrels. The entire groups varies by as much as the often quoted barrel length variations. My three 7-08's all with 22" barrels, same.

I suspect that velocity numbers for factory ammo have at least as much "hot air" as a political promise. Handloading manuals about the same.

The worst case is Remington ammo for my .35 Whelen. Even in my CDL/24" barrel I'm short close to 200fps.

So, load up and shoot. If the ammo groups good, check POI at longer distances. Velocity is "you get what you get". If that's not fast enough, load your own and add more fuel, (you're on your own with that one). Or, get a bigger case volume and start over.
 
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