Well I tested 14 combinations through the chronograph and grouping. I learned some things and the new chronograph is awesome…..really helps working up loads because I want to simulate the ammo the BDC is based on so I am looking for 3100fps on 55 gr fmj , 2900fps on 69 gr SMK’s and 2700fps on 75gr HPBT.
Things I learned:
Don’t let your buddies put you leaky coffee mug in with the finished load data….all readable still but look like crap
14 loads are too many for the day. I was mixing up data a little because the order on I had the targets on the board and learning the features on the new chronograph.
Barrel was hot and stayed warm to approaching hot, so if I did the whole cool down thing then it would have taken a few hours longer…..and really that is not realistic for the role of this rifle , I need to know how this rifle shoots hot, it’s not a paper puncher regardless of how much paper its been punching since I got the scope….fighting rifle first, fighting rifles are either cold or hot and not allowed to cool till fighting stops and since the barrel is meant for that , that’s how I am testing it
I need to include less people while doing this, love my buddies but between them talking to me while assimilating my data and shaking the shooting bench while I’m shooting I think I would be better off on concentration and accuracy but am satisfied that I got the job done for the most part.
And getting everyone’s gear and themselves out the door is a effort on its own so we got out there just as heating air turned to gusty wind as the air heated for the day. Morning is calm and if it were just me or me and one then I could easily get out there in calm morning air……not that it make a hell of a difference at 100 yards but some gusts at the end were stout.
My rifle doesn’t like Hornady 75gr HPBT’s…..they shoot descent but they are the second worst grouping projectile out of the main 5 projectiles I have been shooting
My rifle loves Hornady 55gr FMJ-BT, it shoots the Prvi Partisan 55gr FMJ-BT decent but the Hornady’s cut an inch off the group , right around MOA at lower speeds and fly an average of few fps faster when all else is the same…..charge, powder, brass, primer
The tightest group was the slowest group of AR-Comp, just below MOA @ 2875fps average and the largest group was the second fastest velocity with H335, just below 3 MOA @ 3074 average using PP 55gr FMJ-BT.
Conversely the exact same load using Hornady 55gr FMJ-BT came in at 1.5 MOA @ 3076 average
All the rest of the 55gr FMJ-BT were Hornady and loaded with H355 at 2 to 1.5 MOA with speeds of 2831 to 2958 fps average
My rifle seems to like 69gr SMK’s.
It shoots the 69gr SMK with AR-Comp powder a little tighter than the Reloader 15 and grain for grain a little faster than Reloader 15.
The 69gr SMK groups didn’t suffer at all from being pushed faster like some of the 55gr loads. It basically stayed 1 MOA with AR-Comp and 1.5 to just below 2 MOA with the Reloader 15, plus the group seemed to open up a touch as the speed went up with the Reloader 15.
The 69gr SMK was 1 MOA with AR-Comp @ 2732 and just below 2 MOA @ 2887 using a bit more Reloader 15. As I researched powders I was sure the Reloader 15 was going to be a more accurate powder than AR-Comp but so far my data is opposite in my rifle.
The Hornady 75gr HPBT came in at 2.3 MOA with Reloader 15 @ 2635fps average……didn’t try any AR-Comp.
So I still need to speed up all loads and see what happens to duplicate the 5.56 military loads the BDC is based on.
Luckily all the groups are all acceptable to me for an AR15 and they aren’t falling apart with speed.
Good news is none of the brass is showing over pressure signs so will pick out the most accurate loads and work with them up till I reach the desired speed and be on from 8 to 800 yards with the flip of a dial…..if I do my part and by “on” I mean head shots on silhouettes at 400 and center mass out to 800….if I ever find a spot to go that far without shooting across draws or canyons.
I recently obtained a range membership that goes to 600, hate public ranges but its only 10 min from my house and I cant find a meadow over 500 yards so what the hell I guess it was only 25 bucks for a year and has 9 ranges including shotgun clays and archery.
Again these were shot off sandbags, like the ones you use for a flood or fox holes
18" stainless steel barrel , 1:8 right hand twist ,6 groove button pulled rifling, rifle length gas system, Rainer Arms Mini Comp and free floating hand guard
1-6x 30mm PA Advanced Combat Sighting System Reticle
Things I learned:
Don’t let your buddies put you leaky coffee mug in with the finished load data….all readable still but look like crap
14 loads are too many for the day. I was mixing up data a little because the order on I had the targets on the board and learning the features on the new chronograph.
Barrel was hot and stayed warm to approaching hot, so if I did the whole cool down thing then it would have taken a few hours longer…..and really that is not realistic for the role of this rifle , I need to know how this rifle shoots hot, it’s not a paper puncher regardless of how much paper its been punching since I got the scope….fighting rifle first, fighting rifles are either cold or hot and not allowed to cool till fighting stops and since the barrel is meant for that , that’s how I am testing it
I need to include less people while doing this, love my buddies but between them talking to me while assimilating my data and shaking the shooting bench while I’m shooting I think I would be better off on concentration and accuracy but am satisfied that I got the job done for the most part.
And getting everyone’s gear and themselves out the door is a effort on its own so we got out there just as heating air turned to gusty wind as the air heated for the day. Morning is calm and if it were just me or me and one then I could easily get out there in calm morning air……not that it make a hell of a difference at 100 yards but some gusts at the end were stout.
My rifle doesn’t like Hornady 75gr HPBT’s…..they shoot descent but they are the second worst grouping projectile out of the main 5 projectiles I have been shooting
My rifle loves Hornady 55gr FMJ-BT, it shoots the Prvi Partisan 55gr FMJ-BT decent but the Hornady’s cut an inch off the group , right around MOA at lower speeds and fly an average of few fps faster when all else is the same…..charge, powder, brass, primer
The tightest group was the slowest group of AR-Comp, just below MOA @ 2875fps average and the largest group was the second fastest velocity with H335, just below 3 MOA @ 3074 average using PP 55gr FMJ-BT.
Conversely the exact same load using Hornady 55gr FMJ-BT came in at 1.5 MOA @ 3076 average
All the rest of the 55gr FMJ-BT were Hornady and loaded with H355 at 2 to 1.5 MOA with speeds of 2831 to 2958 fps average
My rifle seems to like 69gr SMK’s.
It shoots the 69gr SMK with AR-Comp powder a little tighter than the Reloader 15 and grain for grain a little faster than Reloader 15.
The 69gr SMK groups didn’t suffer at all from being pushed faster like some of the 55gr loads. It basically stayed 1 MOA with AR-Comp and 1.5 to just below 2 MOA with the Reloader 15, plus the group seemed to open up a touch as the speed went up with the Reloader 15.
The 69gr SMK was 1 MOA with AR-Comp @ 2732 and just below 2 MOA @ 2887 using a bit more Reloader 15. As I researched powders I was sure the Reloader 15 was going to be a more accurate powder than AR-Comp but so far my data is opposite in my rifle.
The Hornady 75gr HPBT came in at 2.3 MOA with Reloader 15 @ 2635fps average……didn’t try any AR-Comp.
So I still need to speed up all loads and see what happens to duplicate the 5.56 military loads the BDC is based on.
Luckily all the groups are all acceptable to me for an AR15 and they aren’t falling apart with speed.
Good news is none of the brass is showing over pressure signs so will pick out the most accurate loads and work with them up till I reach the desired speed and be on from 8 to 800 yards with the flip of a dial…..if I do my part and by “on” I mean head shots on silhouettes at 400 and center mass out to 800….if I ever find a spot to go that far without shooting across draws or canyons.
I recently obtained a range membership that goes to 600, hate public ranges but its only 10 min from my house and I cant find a meadow over 500 yards so what the hell I guess it was only 25 bucks for a year and has 9 ranges including shotgun clays and archery.
Again these were shot off sandbags, like the ones you use for a flood or fox holes
18" stainless steel barrel , 1:8 right hand twist ,6 groove button pulled rifling, rifle length gas system, Rainer Arms Mini Comp and free floating hand guard
1-6x 30mm PA Advanced Combat Sighting System Reticle
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