The Long and the Short of it

The Long and the Short of it

 

Article written by Robert J. Stokes 

The Blaser R8 rifle can be had with several barrel lengths, the standard profile barrel for standard calibers is 22 ¾” but an optional short barrel is also available. The short barrel is 20 ½“ and comes at a higher cost, about a 40% premium. The short barrel is handier, but how much velocity do you loose and what about accuracy?

I thought it might be interesting to take a look at these two questions because I don’t think these factors are well understood. My favorite R8 barrel is a short, semi-weight, fluted barrel with sights chambered in 9.3X62. I’ve found this barrel to be wonderfully accurate and handles like a dream. But I’m often asked, “don’t you give up a lot of velocity with that short barrel”? And “surely it can’t be as accurate as a longer barrel, I bet you give up a lot of range don’t you?”

Since I also own a standard 17mm R8 barrel in the same caliber, I decided to see just exactly what I do give up by using the short barrel. I know it isn’t as much as a lot of people think. But I also didn’t know exactly what the penalty other than cost is to achieve that better handling. So let’s take a close look and see just exactly what the performance difference really is.

So off to the range I went with four selected loads, two factory, and two hand-loads. Since this is a hunting rifle I decided to run this testing with a hunting scope, a Zeiss 3-12X56 HT. I also brought along my Lab Radar, Doppler radar chronograph to see exactly how much speed and range is given up with the short barrel.

The loads I chose for the test were as follows;

  1. Nosler Custom 250 grain Accubond Factory Load.
  2. PPU 285 grain Soft Point Factory Load.
  3. Nosler 250 grain Accubond Hand-Load using IMR4895 powder.
  4. Nosler 256 grain Partition Hand-Load using IMR8208XBR powder.

These are all loads that I have used and know are reasonably accurate. The 250 grain Accubond hand-load was developed and tuned for the short barrel so that does give it a slight unfair accuracy advantage. And as you will see, it was, as epected the most accurate load tested, but as you will also see, it wasn’t a significant factor when evaluating the overall accuracy of the two barrels. They are actually quite similar, just with different preferences.

So first lets look at accuracy. Again, since this is a hunting rifle, not a match rifle, I decided to look at only three shot groups.  This is statically speaking, an insufficient number of shots to pinpoint the true accuracy potential of these two barrels, but it does give a strong indication.

All groups were fired at 100 yards from the bench and measured in inches

Barrel Load 1 Load 2 Load 3 Load 4
20.5” .907” .910” .339” .753”
22.75” 1.120” .465” 1.090” .428”

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It is clear the short barrel prefers the lighter, 250 grain Nosler Accubond bullet and the long barrel prefers the heavier 285 and 286 grain bullets. But on average they are both well under one inch at 100 yards. The short barrel averaged .727” and the long barrel .776”. Statistically there is no difference; with a wider selection of loads either barrel may prove the more accurate. The short barrel will consistently shoot it’s preferred load with all shots touching at one hundred yards. And will shoot  2” groups at 400 yards. I’m sure I could develop a load that will shoot just as well out of the longer barrel; it’s only a matter of time and materials.

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Most accurate load from 20.5” barrel


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Most accurate load from 22.75” barrel

Now what about speed, what is the velocity penalty of the short barrel?

Muzzle velocity is measured in feet per seconds.

Barrel Load 1 Load 2 Load 3 Load 4
20.5” 2329 2178 2436 2300
22.75” 2384 2219 2479 2334

So the longer barrel is faster but only by an average of 43 feet per second. And just exactly does 43 FPS slower mean, is it significant? The Doppler radar can help us understand this by measuring the rate the bullet slows down once it leaves the barrel. As it turns out, a bullet fired from the longer barrel slows down to the same speed as the same bullet leaves the muzzle of the shorter barrel very quickly. So quickly in fact that it only takes 24 yards until the bullet from the longer barrel is going the same speed as the bullet leaves the muzzle of the short barrel. So that’s it, all the difference is in terms of the speed and therefore the energy contained by the bullet is a distance of a mere 24 yards. This is not very significant.

So this testing leads me to the conclusion that there is no significant difference between the 20 ½” barrel and the 22 ¾” barrel in terms of effective range. Both are more than accurate enough, both deliver more than adequate energy, for any game animal in North America or Europe, out to further than most of us can shoot accurately anyway. So use whichever length you like. The biggest penalty you will pay is the price premium. Unless, that is, you find the extra 24 yards in range significant to your hunting situations.

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