Q:

Cast bullets, power and frame flex, a thin precarious line

I shoot long range, 150 yards and further with cast bullets in the AF platform.

I use a dechoked LW 25 caliber barrel, a custom stretched Talon SS frame, a heavy spring and hammer to power a Dyotat valve and cast bullets from 56 to 75grains at 115 to 125 FPE and I do it tethered usually around 3400 PSI.

I get groups at times around MOA for 5 shots at 150 yards and at times 285 yards. I will paint 6 small dots on a 3×4 sheet of black painted steel and shoot 6, 5 shot groups, go down and measure them, re paint and do it all over again. When everything falls together, I take a picture of them and post them for you.

Problem is they are not consistant, one group will be 1.75 inches and the next under identical conditions will be 5 inches. It is frustrating beyond belief.

One day I will get very tight groups, think I am on to something and the next outing it all goes to shit again.

I get a lot of PMG’s and emails from shooters wanting to know how to modify their Condors to shoot cast bullets at high enough FPE to be accurate at long range.

I explain to them they need to get a unchoked barel, or cut thier choke off, a bigger valve, Dyotat’s 25 caliber valve on your body being the best IMHO, a higher fill pressure and to open that big valve against the high pressure, a stronger spring to power a heavier hammer.

The problems is, the AF platform, as WOK likes to mention was not designed for this, and he is right.

The frame has flex problems, and again WOK has pointed this out in the past by telling us to put a laser on the rib of the tube and then shoulder the rifle with a strong grip and watch that laser dot move against the crosshairs.

Now I read folks who say they have not problem with POI change induced by frame flex, but they are not shooting 150 yards with 75 grain cast bullets powered by heavy hammers and springs, in short they are using their rifles for what they were designed for, 65 FPE and under.

And they have not done the laser test.

Problem is for long range you need cast bullets, Diablos don’t cut it, and you need high FPE, the AF platform has trouble providing this. You need 115 or more FPE to resist wind drift and reliably throw high BC cast bullets down range for any consistant groups.

Simply put the frame is flimsy. It is light aluminum, has dimesions that vary badly, has a poor barrel mounting system and a Power wheel cutout that is nothing but sucidical for frame/barrel integrity.

Before you get all hot under the collar, ever look at a benchrest PB or a Hi power competition PB?

They carry heavy thick barrels and they sleeve the actions, if it is a AR 15 based rilfe, it has a heavy barrel and a tube forearm. The AF platform has none of these action and barrel stiffeners, the tube on the AF does not float the barrel like on a AR, it bears directly against the barrel bushings and thus moves the barrel when the frame is flexed.

Practionors of those disciplines would laugh at the AF line and the flimsy components, these flaws result in the frame flexing when held in different postions between shots or shooting seccions, and vibration and stress directed towards the barrel by the impact of ultra heavy springs and hammers.

The frame needs work, the hammer spring system is what it is, it is how the rilfe works and can’t really be changed in my opinion, and every single time I step up to heavier hammers and heavier spring, power goes up and accuracy goes south.

Part of these problems can be remedied thru strengthing the frame. For conventional use, ie, what the rifle was designed for, the WOK guard works very well, the Maddog stock does better yet if you can live with how it changes the balance and looks of the rifle.

But none of this fixes the impact of heavy hammers and springs and how that stress relates to groups at long range.

I have this week tried putting a AF Tri rail on the carrying handle and on the rib in place of the forearm, I saw no improvement.

I think the cottage industry needs to step forward and create a stiffing system that either replaces the frame with a steel tubed frame without a Power wheel hole, which is a serious defect in the integrety of the frame or a thick unflexable Picatinny rail that will run the full length of the under and upper ribs. Or a WOK type guard that either extends to give a free floating forearm and hopefully is made of steel.

But in the end what we need is a stiff steel tube with fire control rails made of steel welded on.

Problems is there are not enough buyers to make this feasable at a reasonable price point, perhaps as this long range game becomes more popular that will change.

All this is heavy, and will really change the ergonomics of the rifle, but for long range shooting at targets this is a good trade off in my opinion.

The power is there, Dyotat has provided that in a reliable remake of the valve for 25 caliber bores, we now need a better aftermarket frame.

I look at fully supported Maddog stocks, and I look a slightly stiffer TJ barrels, but I just can’t justify the finacial outlay when I can get a Haley Scandalous that will shoot circles out of what I have come up with so far and is made from the start for long range with cast bullets and is in the same price range once everything is bolted on a AF platform purchased for that purpose..

I am not saying throw your AF rifles in the junk pile, if you want more power, use Dougs valve, a slightly heavier hammer and spring put on a WOK guard or a Maddog stock, use Jerrys slugs and be satisfied with 100 FPE, because right now, with what we have for frames, your throwing money towards the wrong platform.

Regards,

Roachcreek

Mods/Machinists

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Viewing 15 replies - 1 through 15 (of 34 total)

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DW,

I think that “frame flex” improvement you made looks awesome. The bottle support looks like a gas tube! 😎

quote roachcreek:

3 of which is literally pencil thin with all this riding on it.RC

I think Doug may have already said this but how much thicker does he machine this section on the .257 barrels. I would imagine since this area is “beefed up” along with the new breech he makes to fit, it would aid “rigidity”!

1.1″ at 350 yards 😯 🙂 That is unreal. How many powderburners could achieve that? That is sub 1/3″ MOA ❗

I’m an HK freak and have noted that the G3 design would show some change in point of aim with long range shooting. In HK’s PSG1 design an approximate 3/8 wide stiffener was spot welded down the sides of the receiver to correct the problem.[imhttp://i1287.photobucket.com/albums/a632/flaxk9/psg1receiver.jpgg][/imhttp://i1287.photobucket.com/albums/a632/flaxk9/g3receiver.jpgg]

Thanks Rob 🙂

quote roachcreek:

Mike,

It appears on the edge should get a few more posts under his belt and review AF history before he decides that AF is such an inovative company.

AirForce makes $500.00 guns that they sell for $600.00, and they do a relatively poor job of it . The system is touted as one with intercahngeable barrels, trouble is the frames and bushings for those barrels are all over the map in measurements.

They also steal others ideas, but don’t despair, they usually muff it when they do, ie., AF’s version of the ETAC, the spin lock.

Or a concept that should have been still borne, the Talon pistol.

Good to have you back Mike,

Regards,

Roachcreek

Thanks for the Welcome Back RC! 😀 😀

And good to see you 2-Fast, and Rob!!! 😀 😀

I did mount the ss into a Mad Dog full length Ultamate stock last week, and there is a marked improvement. Big Time!
Sadly, the bottle is not supported. I talked to the maker, and he felt it wasnt’ somthing that would help. But you know me. It’s getting done for testing. 😉

Lama came over for supper, watching the F-1 race, and a little shooting. He saw what the ss in the new stock could do first hand.
One group, (The first fired with JSB’s) right under 1/4 inch at the 80 yard range.
Did it again with the 21 gr Kod’s. .231″ if I rember right.
Sadly, this was all with the 24″, .22 bbl. in place. It shoots much better with the .25 Bbl. and the 25.4 gr JSB’s but AOA hasn’t sent me the shipment of .25’s yet. (I’m ruinning dry!!! 👿 )

When I recieve some, I will stretch the range out a mite, and see what She can do! 😉

Mike

[quote=”DogWood”]This was my solution to the frame flex problem

I drooled over that setup for years, too… For whatever reason, I just thought it looked great and still do.

This was my solution to the frame flex problem

Rather crude by my current standards, but all I had was a hack saw and drill press
.25″ Aluminum plate screwed together to beef up the frame and a stock to take the presser off of the bottle.

painted

I designed this in solid works and was thinking of machining it on my CNC mill, but I ended up selling the SS before that happened

probably should have just cut off the forearm portion and produced the frame reenforcement and stock, oh well.

I got the notice that work has begun on my Haley Scandalous, so I took the 5×15 3200 off the Talon SSS and put a 2×7 Burris fulfield on it.

It shot okay at 40 yards with the medium spring, but at 150 yards I could see the valve was not opening enough.

I reinstalled the heavy spring and played with the PW until I was getting right at 120 FPE with the 56 grain cast bullets, shot a cople of 5 shot groups that were from 3 to 5 inches aat 150 yards.

But the rifle is a great 50 yard or so air gun for what goes bump in the night, but for long range the Haley beats it hands down in every regard.

So bottom line, I am not going to spend any more money on it, it does fine for what it is, a medium range powerhouse.

I just got an email from Reba, one of the owners of a 257 Haley similiar to mine sent her a 1.1 inch group, shot at 350 yards!

Regards,

Roachcreek

“Gentlemen, we can rebuild him. We have the technology.”

“Better… stronger… faster”

😆

Sounds like you got a plan. I dig the Excaliber. Looks like the bottle length wouldn’t be an issue. Seems you could use low/medium rings and using the butt on the stock would align everything up in a more natural position. Hard to tell from the photos. The Ultima stock kind of looks like the same deal.

Tethering does change dynamics a bit 😆

Benneeboy,

I am actually liking the looks of the Excalber verison, with the angled tank adapter it should place the bottle back far enough to allow for the drop of the adapter/bottle.

I am thinking one would have to add a spacer to the butt because the tank will be longer than the stock in the pictures.

I had the pistol grip one before, and it made a big difference as far as frame flex.

But alas I did plastic surgery on it to graft a AR 15 grip to it and it died on the operating table.

The other problem is of course weight, but shooting tethered at 150 or 285 yards weight is just a plus.

RC

quote roachcreek:

When you say “standard”, do you mean the standard Maddog or the AF stock?

RC

Sorry Charlie! I meant as in a tradition style rifle stock. Like the mad dog would give a af rifle.

Tof,

My old pistol grip Maddog was much more stable than the WOKGuard, just uglier than a hicky on a hemmeroid..

Envision that for a second.

But once you have the Maddog stock stable, whether glassing in Rebar in the forearm channel or just glassing in the entire front tube, you still have to deal with that jar from the heavy spring slamming that heavy hammer forward to hit a plastic breech which in turns hits the tophat and bounces forward and the fact that there is 5 inches of barrel hanging out there, 3 of which is literally pencil thin with all this riding on it.

But still I think the Maddog Excaliber stock being fully supported, or isolating the bottle and frame from hold stress is a step in the right direction.

I see improvement going back lighter springs and using the same hammer, the Talon SSS just broke down before I could give it a comprehensive test.

Before I committed to this thread, I shot 15 5 shot groups at 150 yards using various positions in addition to a harris bipod. All shots were used using a tethered and regulated 44 cf tank.

RC

RC,

I definitely agree with your assessment on the Air force frames and gun.

A lot of what you said is why I’ve built my new talondor the way i did (or Doug built it…lol).

The forearm got an EXTRA mounting bolt so it has 2 instead of one for added rigidity. It snugs to the underside of the frame more. I also had Doug pin it to where it was snug to the front of the Wokguard. Again, more rigidity.

Then i added the WOKGAURD. For EXTRA rigidity!

Then there is the 1 piece 6061 aluminum barrel bushing. For EXTRA rigidity, strength!

Then there is also the frame end cap which is SNUG fitted to the barrel and the frame and butts up to the end of the 1 piece barrel bushing. For EXTRA rigidity and strength!

Then i bought a DPMS ar15 adjustable pistol grip with HIGH beaver tail and shaved down the beavertail with my Dremel to allow the bottle to sit just on top of it. Again, for EXTRA rigidity and support!

I feel as though these mods have made a huge improvement. Has it relieved ALL of the frame flex? I don’t know. But i can say for three weeks straight (4th week coming up soon), the gun has held POI and i’ve done MINOR scope adjustments even when out in the 99 degree weather!

With the Mad Dog stock. Since i don’t own one nor have i seen one, i wonder if it fits the condor frame snug and supports it from BOTTLE end to FRAME end? Then, if it was to mount to the air force frame via 2 through 3 screws along its length, if that would not totally take out frame flex? If the MD stock was to totally encapsulate the bottom of the Airforce frames and have multiple mounting/hold down locations, i don’t see why it would not eliminate all flex. Heck, throw in a long 1 piece barrel bushing along with the mad dog……………VOILA….. 😎 😆

All of this on top of a light and CONSISTENT HOLD should take care of frame flex. 1 hand on the pistol grip and the other hand sitting by idly.

It would even be nice if the frame was TWICE the wall thickness of the current setup.

When you say “standard”, do you mean the standard Maddog or the AF stock?

RC

I think the “standard” rifle stock design is one of function.

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