That....fredo--love this build. Just for numbers ,20 yrs ago I built a standard 22-250 AI with the sole purpose of shooting a p-d at 1000 yds. I know that to-day that is not all that of a big deal. I don't know if using a broughton 27in 5r 9 twist with the bore coated with" bore coat" is why it works, but with about 43grs of r17 I can push a 75 a-max or 75 vld Berger right at 3725 fps. I was told on here that using q-load I should be in the 70,000 psi range. I don't have any smile's on my brass and no hard bolt lift. I took one new WW brass and keep loading it until I had poor primer pockets. That took 15 firings. The rifle was a 1/4 inch gun when new, it now has just over 1000 rds down it and is starting to open up. I have had no trouble with stabilization or bullet separation. My original thought when I built it with the 27 in barrel with 5in tenon was that when the throat gave up I would cut 3in off the tenon, have a 24in barrel and chamber it for a standard 22-250. Just getting to this cross road now. But I think with the low prices of x-caliber barrels I would just delegate this old barrel to another fat tomato stake and start over. Just my experience.
Ya that's some real velocity for sure. I just finished a 22-250AI with a 30" barrel and getting in the mid 3500 range with the 80s and thought that was impressive. I'm certain it will be lower once accuracy becomes my goal. Break in period right now as well as fireforming brass so I'll know more later on.That....
Is getting so dangerously close to unbelievable.....
I’m not calling you a liar at all....
I’m saying you own a unicorn
Im sorry but I don't see the hotrod in this. If your going to do all of this why not go with a 1-13 or 1-14 twist and shoot 60 gr or maybe 55 gr and then you will have hotrod speed.
Maybe its just me but 3750 just does not do it for me. 4100 to 4200 now that's a HOTROD.
4088 & 4035 are pretty much all out hot rod speeds for the 75 grainer in a .224. Not sure but when guys talk about the 22 Cheetah moving 50-55s at well over 4000 fps being speed demons, I'm thinking the 75s at over 4000 also qualifies it as one as well.Im sorry but I don't see the hotrod in this. If your going to do all of this why not go with a 1-13 or 1-14 twist and shoot 60 gr or maybe 55 gr and then you will have hotrod speed.
Maybe its just me but 3750 just does not do it for me. 4100 to 4200 now that's a HOTROD.
20, funny you should ask!
Happens that I was just messing with QL to get these latest #s to match.
1. I adjusted powder temp
2. Weighing factor already adjusted DOWN to .33 (recommended for "overbore" cases)
3. Case volume trued, per avg. of five, 1x fired cases
4. Initial start pressure set to 7200 psi (for bullet 'jammed')
Given those adjustments, projected velocity was still LOW.
So...I then adjusted 'Ba' factor UP to where projected velocity match from Magnetospeed.
REMEMBER, this is a 75 GRAIN, .224 caliber BULLET
![]()
Not any kind of QL guru, just stating my methodology for working with an otherwise 'unknown' cartridge!
With QL now 'tuned' the best I can for the REDLINE, it shows that load above was running in the vicinity of 69K psi. TOO HOT!!!
Primers had a slight cratering, but the bolt lift and ejector mark are dead giveaways:
![]()
Now that I've got a decent 'tune' on QL, I should be able to dial down to a safer pressure. Furthermore, can reference the 'Pmax / Z1' relationship for a given charge. Also, can look at OBT #s for the 27" barrel to see if/what charge looks best on that.
Not relying on any ONE source, just nice to have as much data to compare against! In the end, the target is gonna tell me what's best...
Sorry to bore yall with QL stuff! Just tryin' to be SAFE & methodical about load development! Kinda sucks to drive an hour to the range to shoot 3 rounds, but I'd rather do that than blow my friggin' face off!!!
Pictures are worth a thousand words. Let’s see what was left..Spoiler Alert!!!
Fredo has initiated the Redline! It was worth the wait.
A secret anonymous source has digital proof of devastating terminal results.
ohhh my! Snert is happy happy happy.
![]()
Pictures are worth a thousand words. Let’s see what was left..