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Hello all,
I'm new to the site and new to the world of the Grendel but already feel at home due to the nature of the beast. I'm a 31 year old honorably retired Marine from North Carolina who can't stand being away from the fields and the woods for too long. I found this site while trying to locate and close with some real life reloading data. Even though I own what seems like every reloading manual they make, the information for where to start and with what to use for this kind of cartridge seems to be eerily vacant. Due to this, I took what I know about burn rates, propellant size, cartridge shape and case capacity to discern what I believe to be one of the best loads for this particular firearm and I wish to share what I've found.
I began building this AR 6 months ago and 2 weeks ago every piece of the puzzle finally came into place. I ordered pieces from around the U.S. to put together a "greater than mil spec" Grendel. From what I had been seeing about the loads others on this site have put together; h335, 8208, X-term, tac and so on, and then by analyzing burn rates vs. peak pressure curve vs. percentage of case capacity filled I made an educated decision for a powder with very good metering capabilities as well as a boost in over-all velocity. H322 became a threshold that has shown some very real and very positive results. Before I came upon this powder for this round, I went through BL-C2, Win 748, and H335 with H335 giving the best velocity results. Win 748 showed some very good accuracy but still wasn't fast enough to give me a 32" holdover at 500 yards as this was my goal with a 100 ttsx. I have put together a few rounds with 120gr. bullets but I do not believe the Grendel was intended to perform the best with 120+ gr. bullets, but this is only my opinion. I am sure that accuracy is better with the heavier bullets pushing the b.c. past the .450 stability barrier, but velocity is very limited with those bullets. Now, I own a 6.5 creedmoor and the 120+ bullets seem to be intended for that cartridge moreover the Grendel, but that is a whole new bag of rats and we won't open that sack here.
Back to the H322. The powder is extruded and seems to resemble varget that has been cut in half. And I think everyone here can attest that Varget is a very accurate powder due to it's extruded form. This fact alone led me to begin developing a max load and a hunting load based on it's burn rate and extruded form. H322 is a little faster than h335 and outperforms it on almost every test I have performed from distances as little as 50yds. to 750yds. I believe this is due in part to it being extruded and h335 being a ball powder though I shoot nickel groups at a hundred yards with this powder in my 5.56 AR so I am not saying it is an inferior powder at all. Different cartridges like different powders and I just don't believe it to be the best for the Grendel.
I began my loads at 27 grains of h322 in lapua brass over cci 450 primers. Initial test confirmed what I expected. Dime size groups at a hundred yards with a muzzle velocity right at 2575fps. After inspecting the brass and primers for damage and found not a scratch, I bumped the load up to 28.5gr. and achieved a MV of 2720fps and knew I was getting close to the velocity I needed to hit the holdover I wanted. I began to wonder, at a hundred yards, if I was pulling shots over the target somehow but knew that I wasn't when I put the first 5 shots through the same hole leaving no indication that more than one shot was fired. This made me really excited. Brass/primer inspection revealed a slight flattening of the primers but no other indicators so I put together a few more loads with increases in .25grain increments to discern where the peak pressure/ unburned powder threshold resided. This is what I found.
H322 Muzzle Velocity Group Size @ 200yds.
under100gr.BarnesTTSX B.C. .359
29gr.-----------2775fps------2" (primers become noticeably flat)
29.25gr--------2800fps------1 3/4"
29.50gr.-------2825fps------1" (tightening up)
29.75gr.-------2850fps------1/2" (solid-flat primers but no extractor marks for75rounds
30.00gr.-------2875fps---------5/8" (very flat primers/extractor marks every other round
30.25gr.-------2886fps---------3/4" (very flat primers/extractor mark every round)
The first thing I noticed once I began to look through the collaborated data is that peak pressure/maximum burn is around 30 grains of H322. According to how the the .25 grain increments work, every .25 gain in powder displayed a 25 fps increase. Once I reached the threshold of the amount of powder able to burn I realized that powder from the 30.25 load went unburned and did not display the expected velocity increase. From that load and extractor mark data I concluded that 29.75gr. seems to be what my firearm likes even though the primers are a little flat. I do not recommend anyone load this up until they have worked up to this load as there are signs of overpressure. I have been reloading for a decade and have had the expertise of 3 generations of military men in my family to lean on for advice concerning pressure signs and grossly over pressurized loads. I have watched my brothers see the signs and still go way beyond to the point of catastrophic cartridge failure where the case actually blows apart in the middle of the case. Luckily, no firearms have ever been destroyed from these "experimental" loads and nobody has ever been hurt, but, one must always remember when loading your own ammunition is that hot metal is harder to remove from your face than it is going in.
Well, it's been a real treat to finally get on here and talk a little about what I've learned. I'm sure that new loads will be worked up in the future and this seems about the best way to build a guide for reloading the Six5. This really is a wonderful weapon to own.
respectfully submitted,
14thMay2012
Wiles, Scot C
USMC-RET
IMG_2716.jpg
left to right
AR 15 Carbine
AR 15 6.5 Grendel 18" Carbine
AR 15 6.5 Grendel 22" Tactical
AR 10 6.5 Creedmoor
MK 14 MOD 0
Hello all,
I'm new to the site and new to the world of the Grendel but already feel at home due to the nature of the beast. I'm a 31 year old honorably retired Marine from North Carolina who can't stand being away from the fields and the woods for too long. I found this site while trying to locate and close with some real life reloading data. Even though I own what seems like every reloading manual they make, the information for where to start and with what to use for this kind of cartridge seems to be eerily vacant. Due to this, I took what I know about burn rates, propellant size, cartridge shape and case capacity to discern what I believe to be one of the best loads for this particular firearm and I wish to share what I've found.
I began building this AR 6 months ago and 2 weeks ago every piece of the puzzle finally came into place. I ordered pieces from around the U.S. to put together a "greater than mil spec" Grendel. From what I had been seeing about the loads others on this site have put together; h335, 8208, X-term, tac and so on, and then by analyzing burn rates vs. peak pressure curve vs. percentage of case capacity filled I made an educated decision for a powder with very good metering capabilities as well as a boost in over-all velocity. H322 became a threshold that has shown some very real and very positive results. Before I came upon this powder for this round, I went through BL-C2, Win 748, and H335 with H335 giving the best velocity results. Win 748 showed some very good accuracy but still wasn't fast enough to give me a 32" holdover at 500 yards as this was my goal with a 100 ttsx. I have put together a few rounds with 120gr. bullets but I do not believe the Grendel was intended to perform the best with 120+ gr. bullets, but this is only my opinion. I am sure that accuracy is better with the heavier bullets pushing the b.c. past the .450 stability barrier, but velocity is very limited with those bullets. Now, I own a 6.5 creedmoor and the 120+ bullets seem to be intended for that cartridge moreover the Grendel, but that is a whole new bag of rats and we won't open that sack here.
Back to the H322. The powder is extruded and seems to resemble varget that has been cut in half. And I think everyone here can attest that Varget is a very accurate powder due to it's extruded form. This fact alone led me to begin developing a max load and a hunting load based on it's burn rate and extruded form. H322 is a little faster than h335 and outperforms it on almost every test I have performed from distances as little as 50yds. to 750yds. I believe this is due in part to it being extruded and h335 being a ball powder though I shoot nickel groups at a hundred yards with this powder in my 5.56 AR so I am not saying it is an inferior powder at all. Different cartridges like different powders and I just don't believe it to be the best for the Grendel.
I began my loads at 27 grains of h322 in lapua brass over cci 450 primers. Initial test confirmed what I expected. Dime size groups at a hundred yards with a muzzle velocity right at 2575fps. After inspecting the brass and primers for damage and found not a scratch, I bumped the load up to 28.5gr. and achieved a MV of 2720fps and knew I was getting close to the velocity I needed to hit the holdover I wanted. I began to wonder, at a hundred yards, if I was pulling shots over the target somehow but knew that I wasn't when I put the first 5 shots through the same hole leaving no indication that more than one shot was fired. This made me really excited. Brass/primer inspection revealed a slight flattening of the primers but no other indicators so I put together a few more loads with increases in .25grain increments to discern where the peak pressure/ unburned powder threshold resided. This is what I found.
H322 Muzzle Velocity Group Size @ 200yds.
under100gr.BarnesTTSX B.C. .359
29gr.-----------2775fps------2" (primers become noticeably flat)
29.25gr--------2800fps------1 3/4"
29.50gr.-------2825fps------1" (tightening up)
29.75gr.-------2850fps------1/2" (solid-flat primers but no extractor marks for75rounds
30.00gr.-------2875fps---------5/8" (very flat primers/extractor marks every other round
30.25gr.-------2886fps---------3/4" (very flat primers/extractor mark every round)
The first thing I noticed once I began to look through the collaborated data is that peak pressure/maximum burn is around 30 grains of H322. According to how the the .25 grain increments work, every .25 gain in powder displayed a 25 fps increase. Once I reached the threshold of the amount of powder able to burn I realized that powder from the 30.25 load went unburned and did not display the expected velocity increase. From that load and extractor mark data I concluded that 29.75gr. seems to be what my firearm likes even though the primers are a little flat. I do not recommend anyone load this up until they have worked up to this load as there are signs of overpressure. I have been reloading for a decade and have had the expertise of 3 generations of military men in my family to lean on for advice concerning pressure signs and grossly over pressurized loads. I have watched my brothers see the signs and still go way beyond to the point of catastrophic cartridge failure where the case actually blows apart in the middle of the case. Luckily, no firearms have ever been destroyed from these "experimental" loads and nobody has ever been hurt, but, one must always remember when loading your own ammunition is that hot metal is harder to remove from your face than it is going in.
Well, it's been a real treat to finally get on here and talk a little about what I've learned. I'm sure that new loads will be worked up in the future and this seems about the best way to build a guide for reloading the Six5. This really is a wonderful weapon to own.
respectfully submitted,
14thMay2012
Wiles, Scot C
USMC-RET
IMG_2716.jpg
left to right
AR 15 Carbine
AR 15 6.5 Grendel 18" Carbine
AR 15 6.5 Grendel 22" Tactical
AR 10 6.5 Creedmoor
MK 14 MOD 0
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