Anyone have one for a TC Encore? Been reading a lot about this round and like what Im reading. Im pretty close to putting a barrel on my Christmas list.
For anyone that has one who made your barrel, length, and thoughts? Oh yeah what are you using ammo wise for deer?
You might find this interesting as for barrel length and velocity.
6.5 Creedmoor- Effect of Barrel Length on Velocity: Cutting up a Creedmoor!
February 22, 2016 Bill Marr 6.5 Creedmoor
, Barrel length
, Barrel length and velocity
, Cartridge Selection 0
Since its introduction by Hornady in 2007, the 6.5 Creedmoor (sometimes shortened to Creed) has established a strong foothold in the US rifle market. The 6.5 Creedmoor balances the excellent external ballistics of .264″ diameter bullets with manageable recoil. (FOLLOW US ON FACEBOOK!)
Left to right, 6mm Norma BR, 6◊47 Lapua, 243 Winchester, 6.5 Grendel, 6.5◊47 Lapua, 6.5 Creedmoor 120 A-MAX, 6.5 Creedmoor 142 SMK, 260 Remington, and 308 Winchester. The 6.5 Creedmoor was originally designed as an across-the-course high power rifle cartridge. While it excels at its intended role, the precision rifle crowd was quick to follow suit and adopt it. Among the common 6.5mm cartridges, the 6.5◊284 Norma has developed a reputation as a barrel burner, 260 Remington has greater case capacity and speed, and the 6.5◊47 Lapua is arguably more accurate with a greater level of panache, but, unlike these others, the 6.5 Creedmoor has readily available factory match grade ammunition for a reasonable price. This allows the new shooter access to a high performance cartridge, without the expense of reloading.
I built a custom 6.5 Creedmoor on a Surgeon action
and was happy with the results. To see how the rifle above was constructed, see Building a Custom 6.5 Creedmoor Precision Rifle
I ended up with a finished barrel length of 22″. At the time that seemed like a good idea, but, I was unsure what I gave up from a longer barrel. Given the success of Rifleshooter.comís other barrel length experiments and the surging popularity of the 6.5 Creedmoor, I decided it would be an excellent candidate for a barrel length and velocity test.
For this experiment, I built a test gun on a Remington Model Seven receiver
with a Green Mountain Barrels .264″, 1:8 twist chrome moly barrel blank.
The barrel is untapered, with cutting index grooves machined every inch. Headspace was set to minimum.
I ordered the following parts from Brownells
Before we get to the test, take time to carefully read the disclaimer below:
The contents of Rifleshooter.com are produced for informational purposes only and should be performed by competent gunsmiths only. 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.
Any modifications made to a firearm should be made by a licensed gunsmith. Failure to do so may void warranties and result in an unsafe firearm and may cause injury or death.
Modifications to a firearm may result in personal injury or death, cause the firearm to not function properly, or malfunction, and cause the firearm to become unsafe.
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.
I selected two different kinds of ammunition to test, a light 120 grain factory load, and a heavier 142 grain hand load.
The light load is represented by the Hornady Match 120 grain A-MAX
. This is a popular round with the factory ammunition crowd, often receiving accolades for performance. All test ammunition was from the same lot number.
To represent heavier loads, I selected the Sierra 142 grain HPBT MatchKing (#1742)
. Iíve had great results with this bullet in both the 6.5 Creedmoor
and 6.5◊47 Lapua. Using new Hornady brass and CCI #200 large rifle primers, I loaded the 142 SMK over 41.8 grains of Hodgdon H4350
. This load exceeds the 41.5 grain published maximum listed by Hodgdon
in their reloading manual
, so it should only be considered safe in this gun (reread the disclaimer above).
The rifle is fired from a bench off a bipod. Five rounds of each type of cartridge are fired at each barrel length and the velocity data is recorded with a MagnetoSpeed V3
barrel mounted ballistic chronograph. The rifle is cleared and the barrel is cut back one inch at a time from 27″ to 16″.
The cut is made with a cold saw. Once the cut is completed, the experiment is repeated, until the rifle looks like it does in the picture below.
A quick note on range conditions. This test was conducted at 23F. This is notable when comparing velocity figures. While modern powder tends to be less temperature sensitive than older powders, the low temperature will undoubtedly yield slightly lower velocities than those expected at higher temperatures.
Results by cartridge.
For the 120 grain A-MAX
, a muzzle velocity of 2961 feet/second was recorded at the 27″ barrel length, and 2728 feet/second at 16″ barrel length, resulting in a total decrease of 233 feet/second. The average loss of velocity was 21.8 feet/second per inch of barrel. The largest decrease in velocity, 61 feet/second per inch of barrel was recorded when the barrel was cut from 19″ to 18″. When the barrel was cut from 20″ to 19″ a 3 feet/second increase in muzzle velocity was recorded. Average standard deviation for was 21.3 feet/second.
For the 142 grain Sierra HPBT MatchKing
, a maximum velocity of 2683 feet/second was recorded at the 24″ barrel length. A velocity of 2663 feet/second was recorded at the 27″ barrel length. At the 16″ barrel length, a velocity of 2505 feet/second was recorded. Velocity decreased 158 feet/second as the barrel was cut from 27″ to 16″, or 14.4 feet/second per inch of barrel length. The velocity reduction from 24″ to 16″ was 178 feet/second, or 16.2 feet/second per inch of barrel length. Average standard deviation was 15.7 feet/second.
How does barrel length effect bullet drop and wind drift?
To show how barrel length affects the bulletís flight path, I modeled both cartridges using a ballistic calculator application. I assumed a 100 yard zero, scope 1.75″ above the bore, and temperature of 59F. The drop in mils is shown for 200, 400, 600, 800 and 1,000 yards. The drift for a full value 10 mile/hour cross wind is shown in mils for 200, 400, 600, 800 and 1,000 yards.
For comparison purposes, I included data for a 308 Winchester (shown as 308/22″/175SMK in the tables below) and 300 Winchester Magnum (shown as 300/24″/190 SMK in the tables below). The 308 Winchester data is taken from my 22″ 308 Winchester match rifle using 175 SMKs
. The load has a velocity of 2670 feet/second, hotter than the published velocities for M118LR in use by the US Military. The 300 Winchester Magnum data was obtained using Federal 190 grain Gold Medal ammunition
in a 24.25″ Shilen barrel
with the observed muzzle velocity of 2892 feet/second. Federal advertises the load at 2900 feet/second. The comparison data is shown in the last two lines of the tables below.
With the 120 A-MAX
, there is little lost as the barrel length decreases from 27″ to 24″ inside of 800 yards. At 1,000 yards, 0.3 mils of elevation and 0.1 mils of drift are sacrificed. Note the 6.5 Creedmoor 120 grain A-MAX
with a 16″ barrel shoots inside of the 308 Winchester 175 grain SMK with a 22″ barrel at 1,000 yards! Impressive!
As noted earlier, the 142 SMK
hand load gained velocity as the barrel length decreased from 27″ to 24″. For purposes of this table, assuming other barrels and loads would exhibit the same decrease, there was no benefit in either velocity, flight path, or drift from a 27″ over a 24″ barrel. The 6.5 Creedmoor with 142 SMK
and 17″ barrel shot inside the 308 Winchester 175 SMK 22″ barrel out to 1,000 yards. The 308/175 SMK outperformed the 6.5 Creedmoor/142 SMK
inside of 800 yards, however, at 1,000 yards the superior characteristics of the 142 SMK
allows it to perform better.