Short barrel (16.5″) suppressed and non-suppressed load development, 147 ELD and H4350 – rifleshooter.com

Short barrel (16.5″) suppressed and non-suppressed load development, 147 ELD and H4350 – rifleshooter.com



I’ve written quite a bit about short barrel precision rifles.  On this blog I’ve built a variety of 308 Winchester, 223 Remington, 243 Winchester, 338 Lapua and 6.5 Creedmoor rifles with barrels in the 16-17 inch range.  In this post, we’ll take a look at a short barrel 6.5 Creedmoor with the relatively heavy 147 grain Hornady ELD Match Bullet and a suppressor.  Short barrels are a trade-off, you’ll sacrifice velocity but gain a lighter more maneuverable rifle.  For suppressed applications, the shorter barrel helps mitigate excessive overall lengths.

The 6.5 Creedmoor cartridge is at home in long barrels.  Take a look in most gun catalogs and you’ll see the 6.5 Creedmoor models typically have barrels 2-4″ longer than the 308 Winchester chambering in a given product line.  While our barrel length and velocity data shows that while the optimal external ballistic performance if somewhere over 24″, the 6.5 Creedmoor is still pretty impressive in a shorter barrel.

My first 16.5 ” 6.5 Creedmoor was a custom Savage 10, built with the following parts from Brownells:

It was a great shooting gun that hammered away with 123 SMKs.  The rifle wasn’t intended for suppressed use, so I installed a blended Vais muzzle brake (you can read about how I built it here).

I wanted to look at the shorter Creedmoor in a suppressed rifle with a shorter barrel and the 147 grain Hornady ELD bullets. Since the Savage above wouldn’t take a can, I used my buddies rifle (thanks, Jim) to gather some data.

The rifle for this test is a newly built 16.5 inch 6.5 Creedmoor.  It isn’t coated yet (you can tell by the mixed colors), but was ready for a trip to the range.  It consists of the following parts from Brownells:

It is a neat, compact little gun.

For reloading information: WARNING: The loads shown are for informational purposes only.  They are only safe in the rifle shown and may not be safe in yours.  Consult appropriate load manuals prior to developing your own handloads.  Rifleshooter.com and its authors, do not assume any responsibility, directly or indirectly for the safety of the readers attempting to follow any instructions or perform any of the tasks shown, or the use or misuse of any information contained herein, on this website.

For this test I decided to use the Hornady 147 ELD, a bullet that is popular with the long range crowd.  While I didn’t anticipate it to shoot as well as the lighter bullets in a barrel this short, I was curious to see how well it would perform.

All ammunition was loaded on Starline 6.5 Creedmoor brass with a large primer pocket.  I used CCI 200 primers and Hodgdon H4350 powder.  Each round was seated with a Redding Competition Die with a Forster press.  All rounds were fired prone, from a bipod with rear bag.  Muzzle velocity was recorded with a MagnetoSpeed barrel-mounted ballistic chronograph.

I fired a five-shot group at 100 yards with each load in the rifle without the suppressor installed, then repeated the test with the Dead Air Sandman -L suppressor installed.  The results are shown in the table below.

For the 147 ELD with H4350 powder, muzzle velocities ranged from 2,374 to 2,486 feet/second without the suppressor and 2,376 to 2,484 feet/second with the suppressor installed.  Standard deviation ranged from 6.0 to 26.7 feet/second without the suppressor and 10.2 to 24.6 feet/second with the suppressor installed.  Group sizes ranged from .723″ (.691 MOA) to 1.271 (1.214 MOA) without a suppressor and from .808″ (.772 MOA) to 1.168″ (1.116 MOA) with the suppressor.  Average group size was 1.014″ (.968 MOA) for the rifle without the suppressor and .912″ (.871 MOA) with the suppressor installed.  Average group size for all loads, with and without suppressor was .963″ (.920 MOA).

The Rite in the Rain target is shown in the image below.

I went ahead and plotted the data I had gathered on a series of line graph.

The graph above shows muzzle velocities for the loads with and without the suppressor installed.  Note the suppressor didn’t necessarily increase or decrease muzzle velocity, a finding that we are noticing across a wide range of loads, cartridges and guns.

Group sizes between the suppressed and non suppressed rifle were remarkably similar again, with the exception of the 39.1 grain load with the suppressor installed.  In this case that load shot significantly better.

I like the 6.5 Creedmoor in both long and short barrels.  If you are running a can like the Sandman-L shown here, there is some merit to the shorter barrel, however, I’d probably stick with slightly lighter bullets.  While some of the 147 loads shot fairly well, they weren’t quite at the level of performance I prefer.

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