223 cal 75 gr Hornady HPBT, in Bushmaster Predator upper.......and a question.

[tljames]

Well guys I think I finally found an acceptable load for the Predator upper! I ended up buying some RL-15, Alliant AR COMP, Winchester W748, IMR 4007 SSC, IMR BL-C (2), and I used powder I had on hand which were Varget,Benchmark, IMR 4064 and IMR 4895.
So there were several different loads at several different charges and SEVERAL frustrating trips afield prior to choosing this load. There are three powders the Hornady manual showed as being the better choices for accuracy in their testing Viht N-135, AA 2495 and Viht N-140. With Viht N-140 being the most accurate.Yet no one stocks these in my area so I'll have to wait until I go to Oklahoma City (110 miles east of here) in order to get these. Yes I'll probably buy/try these before I'm satisfied.
So far 25.2 gr of BL-C (2) is the winner. I fired a group after a LONG day of testing and this was the result


{NOTE THE FLYER}

I then went home, cleaned the rifle WELL, loaded 50 more and went to the field the next day. I chronyed the first 5 rounds


Then on a bore which had cooled and only had 5 rounds through it I loaded 11 rounds and fired 10 for group

I was sick, yet I realized I had REALLY cleaned the bore the evening prior so I wasn't crushed yet. A buddy went with me and we worked on a couple of his rifles and loads and I had brought some extra ammo so I fired a few strings through my rifle trying to dirty it up a bit. The next group test was better but still poor Then as the day grew late I loaded my last 4 rounds of test ammo and fired {NOTE THE FLYER}


NOW we're getting somewhere! Ok in both pics with decent grouping you notice a flyer, me too!
The last round out of the mag flys! I don't understand it, I don't know if it pressure difference, bolt locking back or me! (Probably me). Yet I normally load one extra round when I group test, so I avoid this event.
So have any of you experienced this or is it just me? On those last four my buddy was watching through spotting scope saying man they're all touching you're doing great.......WTF! You really sucked it up that shot! Yet I didn't care because it seems to happen every last round. Any Thoughts
Thanks All Thomas

[Orlando]

Are you using a bipod or front rest?
You using a standard trigger or Match?
Ever tried any of those loads farther than 100 yds and see how they do?
Seems like my first rd will be the flyer not the last

As for your 10 rd group, horizontal spread is usually the shooter not the ammo

[tljames]

OK, thanks "O". My next trip is going to be at 500 yds. I have to wait a couple of weeks because "Spring Turkey" season opens on the 6th of this month and the landowner where I shoot will be out hunting. Gives me time to get some things done around here too. "Like mow the yard" lol Thanks! Thomas

Shooting off bags rested on a bench. I do catch my self letting the rifle "roll" now and then, but usually realize it on the shot.

[Orlando]

First off I am no shooting expert:
To get those tight groups consistantly it take practice. I would suggest for testing loads shoot off a lead sled, this takes away alot of variables . You could have a perfectly good load and have a bad day shooting and throw the load out. You end up chasing your tail
Also suggest a good trigger if you dont have one, it will make a differnce
Again, that 10 horizontal group spread looks like shooter error, is your scope AO adjustable?

[tljames]

I can't use my Lead Sled because the backbone isn't "offset" hence the pistol grip rests on it before the rifle contacts the sled. I use Caldwell bags underneath the front and rear of rifle. I have a Timney trigger in this rifle, about 2.5 lbs and just a tick of creep. The Scope is a Mark AR 3-9x40mm T2. 1/2 MOA with mil dots. The lots of practice is definitely where I fall short. Getting a good cheek weld on an AR is a whole new experience for me. Hunting rifle no problem, but I must work and adjust each time I look down my AR, to get proper eye relief. (just not accustom to the straight line of sight an AR has) Thinking about an adjustable target type buttstock, just to tight to buy one right now. So I'll keep playing and practicing and update all on future trips. Thanks "O". Good Luck and Good Shooting All! Thomas