Over the last few years the 6.5 Creedmoor cartridge has become increasingly popular among precision rifle enthusiasts. However, availability of cases was limited to only a few manufacturers and shooters desired better case life and higher quality. Alpha Munitions brought their version of this cartridge brass to market and took a step that may up the bar for all manufacturers: All of their cases come in high quality reusable packaging to not only provide protection during shipping but during the entire life of the case. This thoughtful step eliminates waste and the added expense of purchasing aftermarket case storage.
Alpha Munitions told us that all of the cases of a particular lot are formed by the same tool ensuring consistent internal volume. While there may be some variation in case to case weight, we were told that internal volume would be the same. We did not have a reliable method to measure internal volume so this is an assertion that will have to be verified.
We received a brand new box of these cases (100 count) directly from Alpha Munitions. We took a sample of these cases and conducted a number of measurements to assess the level of manufacturing consistency. Additionally, we subjected a case to a durability test to see how many repeated reloading cycles it would endure. We were primarily interested in the ability of the primer pocket to remain tight as loose primer pockets are a common complaint among those who reload for the 6.5 Creedmoor. Alpha Munitions brass has a large primer pocket and we wanted to see how it compared to other brass with large primer pockets. Comparing Alpha Munitions durability to Lapua’s 6.5 Creedmoor brass which has a small primer pocket would not be an apple to apples comparison. All things being equal, a small primer pocket is more durable.
The primary objective of our test was to assess the durability of the Alpha Munitions offering. We also gathered data indicative of potential accuracy. However, we did not perform specific accuracy tests due to the many variables associated with such an undertaking.
Anecdotally, shooters are getting 6-8 reloads from most 6.5 Creedmoor brass on the market. We spent about an hour on the phone with the principals of Alpha Munitions to discuss their approach to manufacturing and their desire to build a very durable case. Based on what we learned from our discussion, we hypothesized that the Alpha Munitions cases would last longer than other cases on the market with a large rifle primer but probably not as long as cases with a small rifle primer.
We did not anneal in order to represent a worst case scenario, but we didn’t expect to see any failures related to work hardening (e.g., split neck).
For our durability test, we repeatedly reloaded a randomly selected case as follows:
- Dillon 550 press with standard tool head
- Whidden full length sizing die with a .288″ bushing and factory expander ball resulting in .001″ neck tension
- Shoulder set back .001″ during sizing
- We did not anneal between firings
- Cleaned the fired case with a paper towel and periodically removed ash from the primer pocket to ensure proper primer seating
- Lubricated the case with Imperial Die Wax and wiped off the wax prior to firing
- Seated the bullet to magazine length and did not attempt to achieve any particular setback from the lands
- Seated the bullet with a Whidden seating die
- Rifle based on a trued Remington 700 action and 26 inch Broughton 8 twist barrel built by RBros Rifles. Factory non-bushed firing pin aperture. Thunderbeast 30-P1 suppressor
- CCI BR-2 large rifle primer
- Hornady 140 ELD Match bullet – this is a popular weight for the 6.5 Creedmoor
- 42.0 grains H4350 powder (note: We have observed hot and cold lots of H4350 – this is a hot lot). We wanted to achieve a similar velocity to our Lapua 6.5 Creedmoor test – 2,871 fps. 42.0 gr of H4350 resulted in an average velocity of 2,872 fps – within 1fps of our Lapua test. This is just another illustration that changing components can dramatically impact velocities – start low and work up!
WARNING: We deliberately used a very stout load for our testing. DO NOT attempt to duplicate. This load was shot in a faster-than-average barrel with a chamber set up for long 140gr bullets. You may not be able to achieve similar velocities — maybe not even close. As with all hand-loading, always start low and work up charges in small increments.
Measuring tools used:
- Digital vernier caliper
- Whidden headspace gauge – measures from cartridge base to shoulder datum. Very similar to Hornady Lock-N-Load headspace gauge
- Sinclair concentrity tool
- RCBS digital scale
- Mangetospeed V2 choronograph
We repeatedly fired the case 15 times at which point the primer pocket loosened to the point that the case was no longer usable. This was confirmed by the ease of which the primer could be seated and the fact that a new primer could be dislodged using a decapping pin and finger force. It is important to note that we started the test with a fresh case – we did NOT use the case that we utilized for load development.
The fact that the Alpha case could achieve a given velocity with less powder indicates that it may have less internal volume than Lapua. On average, the Alpha cases were 8.37 grains heavier than the Lapua cases which is another indicator that the Alpha cases have less volume. As mentioned earlier in this article, we did not have a reliable method to measure internal volume. The fact we used a different primer (CCI BR-2 vs CCI 450) could have been a contributing factor as well.
There was cratering of the primer that we normally observe even with mild loads shot in factory Remington 700 actions. The primer had very slight flattening but the radiused edge was maintained. There was no evidence of gas leakage.
Case after 15 firings
As we didn’t anneal we had to periodically adjust the sizing die to maintain shoulder setback due to spring back of the work hardened brass. After 15 firings the neck did not split.
We achieved an average muzzle velocity of 2,872 fps. This is a very respectable speed for a 140 grain bullet.
We measured weight, base to shoulder datum, neck runout, and overall length of 31 randomly selected cases:
||Base to Shoulder Datum (Inches)
||Neck Total Indicator Runout (.001 Inches)
||Case Overall Length (Inches)
Our hypothesis was confirmed. The level of durability exhibited Alpha Munitions exceeds what reloaders have reported from other brands of 6.5 Creedmoor cases that utilize a large primer pocket (typically 6-8 reloads before the primer pockets come loose). Alpha Munitions has addressed a main concern of those wishing to reload the 6.5 Creedmoor cartridge – poor case life.
We also believe that shooters might be able to safely push their bullets significantly faster than they typically could with less durable 6.5 Creedmoor cases. This hypothesis will have to be confirmed through more detailed testing and field experience.
The measurements we took of 31 randomly selected cases indicate a high degree of manufacturing consistency. It is generally accepted that potential accuracy and manufacturing consistency are positively correlated. Base to shoulder datum measurements were exceptionally consistent and better than what we saw with Lapua. Compared to Lapua, Alpha Munitions exhibited more variation in weight, neck runout, and overall case length but these differences were slight. One could reasonably argue that these differences would not have any impact on accuracy considering that a reloader will be resizing and trimming their cases.
The fact that any given lot of Alpha Munitions brass uses the same tooling to ensure consistent internal volume is an intriguing one. We’re not aware of any other manufacturer that does this. Once we find a convenient and consistent way to measure internal volume, we will perform some additional testing.
Overall, Alpha Munitions is providing a very durable case that is limited only by the use of a large rifle primer – we would encourage Alpha to explore the use of a small rifle primer. Their manufacturing methods give them a degree of agility that larger manufacturers do not have. As such, we would encourage them to manufacture cases such as 6SLR that require forming of a parent cartridge (.243 Winchester). Naturally, we would encourage them to offer these cases with small rifle primer pockets.
You can learn more at Alpha Munitions.
Editor: Ed Mobley (firstname.lastname@example.org)
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