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Pakprotector
09-18-2013, 09:17 AM
I have seen the long nose, so called 'bore rider' shapes...but for example, in a .224 the usual diameter of this nose is a wee bit smaller than the bore( .218 on a .219 bore ). Excluding the issues it might cause a boolit loaded gently in a brass case, is there any potential benefit to running a bit into the rifling...say a .220 nose on a .219 bore?
cheers,
Douglas

roachcreek
09-18-2013, 04:29 PM
I have used a bore rider years ago, the 457125 in the 4570 and 45100, real PITA in that with a press type sizer it was easy to expand that soft nose and you find yourself on the firing line with a pocketknife trying to whittle down the nose to fit in your bore.

Douglas, what I try to do is to incorporate that same fit into my lead when I polish it in with a 1/4 inch dremel crayex bit. I start off with several slugs to use as gauges as I polish the lead in, I only use the slugs one time as a gauge as your going to change the dimensions as you push them in to see if they fit.

You have most likely read my statement that "the bullet needs to fit like a cork going back into a wine bottle." To try and thumb those bullets into the rifling becomes a painful effort in a short time or at least it was for me. Trying to force them in with a hard flat object works poorly also as it deforms the steering end of the bullet, the base.

So unless your willing to buy a lot of molds to find one that will do that, my vote would be for a proper lead cut into your bore.


BTW I just bought that Herters 25/80, ugh, just could not resist it.

Pakprotector
09-18-2013, 05:29 PM
BTW I just bought that Herters 25/80, ugh, just could not resist it.

I was only tryin' to help...LOL

If you have to polish and fit the leade, then it would seem that what I consider looking for is already happening.

On the base deformation, the 22 cal is getting a retractable bolt; solid end that will move the boolit to just past the far end of the transfer port, and pull back against its lock stop leaving nothing in the way of airflow. I like the side benefit of offering smallest chance to wreck the back of the boolit.

I am acquiring some gas checks to experiment with too...:) The 225107 arrived today, and after cleaning and one heat/cool cycle I made a few boolits. They look quite fine. Now to wait for a 225438, and a....
cheers,
Douglas

roachcreek
09-19-2013, 09:29 AM
Douglas,

Another path I have taken, was the Hoch tapered nose pour bullet. In my 45/100 Sharps I used the 550 grain bullet and it was tapered to do exactly what you suggest, it had three grease grooves outside the case and like my prelubed air gun bullets, the ammo had to be carried in a sandwich baggie, but it was the highwater mark of my BPCR days, or would that be craze?

With the Haley I tried a 257 Hoch tapered nose pour mold. It cast a very consistant weight and made beautiful bullets, but the desing of the mold ,combined with the lighter 105 grain bullet, made them very difficult to get out of the mold, and I the end the NOE outshot it.

So the best solution so far is that lead polished in with the taper in the lead.

BTW there is a very interesting 40 grain 225 caliber bullet mold on Ebay this morning, one enabler to another.:)

Baja_Traveler
09-19-2013, 10:12 AM
So, am I reading this correct? You are going to use a 225107 in your 22 air rifle? That would be very interesting - I'd like to hear the results of that one. I have that mold, so maybe I'll give it a try in my Disco if such a thing will work...

I've been thinking lately (with the advent of our new Airguns section here) about getting some group buys together for airgun specific bullet molds. Now that I'm getting excited about big bore airgunning the cost of purchased ammo is just crazy - when I'm used to pouring my own for just pennies, a $100 mold pays for itself in no time.

roachcreek
09-19-2013, 10:42 AM
The problem your going to have with cast bullets in air gun barrels is the groove diameter is much smaller and most air gun barrels are choked and have a much slower twist, neither of these issues results in stellar performance on paper.

You can get custom molds made for your groove diameter, and that will help, with sizing down, lets say a 257420 which drops at around .261 to .255 is difficult to do and still retain good accuracy, but it can be done.

Also cast bullet barrels need to be cut for a lead or you will not be able to chamber the bullet, once that lead has been cut, the rifle will not shoot as well with pellets..

So it is not quite as easy as just dropping a bullet in the barrel and going hunting.

Best results will always be with using a fire arms barrel fitted to your rifle, and having a power plant that will shoot the bullets fast enough for good accuracy and performance. That is why many cast bullet air guns are 2 or 3 shot affairs, or in the case of the Condors converted to TJ barrels a 10 shot rifle.

Baja_Traveler
09-19-2013, 02:05 PM
Interesting reading, and I'm learning alot.

So i'm thinking I want an air rifle specifically suited for shooting squirrels and prairie dogs from 50 to 150 yards out. There are several places we hunt where the farm properties are close enough that the report of my .204 would be very annoying, and we do not want to wear out our welcome. Most of my shooting buddies have bought the 17 HMR rifles to solve this issue, but the cost and availability of the ammo is a real turn-off to me. I'm wondering if there is a .308 air rifle that would be suited to the task using a 311359 mold intended for the 30 carbine.
I see on the Quackenbush site someone did an article using his Exile rifle with a similar boolit but only getting groups of 1.1 inch at 40 yards. Take that out to 100 yards and I'd be better off with a 10/22!
Any recommendations on something to fill that need? I'm still going to pick up a 22 hornet for the job (the reason I have that 225107 mold), but it would be fun to show up with an air rifle - and the beauty of it is we shoot from benches next to the road, so I could shoot tethered no problem. I already have 2 4500 psi HP scuba tanks to use.

roachcreek
09-19-2013, 02:21 PM
I have yet to see anyone posting very tight long range groups with a DOQ, perhaps they don't own digital camera's or they don't shoot all that well.

The thing with air gun and cast bullets is that we are stuck with being subsonic, yes we can exceed sonic, but only slightly and when we drop back down accuracy goes down the drain.

As a result having a caliber that will get us close to transonic and still be heavy is the goal.

My Haley will take a 257420 to 1145 which is supersonic where I live, the modified Condors with Dyotat vavles and TJ are around 950 to 1000 FPS with the same bullet. Either a 257420 or a NOE 80 grain have been proven to be sub to 1/2 MOA for these rifles.

I expect RLAirguns to produce a 257 TJ barreled Condor in the next two months with a Maddog stock as a complete package, knifemaker on the TAG forum has one and he gets half inch groups at his 80 yard range.

For a 30 caliber rifle try Brent at Extreme air guns, I have not met him, but he is said to be very easy to work with and he makes a very nice 30 through 45 caliber rifles.

If I am lucky and the wind gods are all smiling on me I get 1.5 inches at 300 yards which is Minute of prairie dog.

The thing is is you have a pile of pure lead or 20-1, I don't like it much harder, and a bullet mold you have as inexpensive and available fodder as you are going to find.

When it shots MOA or under and approaches 150 to 200 FPE just makes it better.

The 257420 at 950 will have a 4.8 midrange trajectory when sighted in at 100 yards and shoot around 16 inches low at 150 yards.

Pakprotector
09-19-2013, 04:47 PM
I am indeed going to run the 225107 from an air rifle. The barrel is a TJ Hornet liner with a 14" twist. The rifle is a Benjamin Marauder, though I suspect the proper work could be done to a Discovery. The Marauder will be packing a 500cc bottle, and a thoroughly modified valve. I also plan to run the 225438, and likely others as I play around. I don't think RC's 615 yard pepsi shot record is at risk, but I suspect it will be just a few tics behind. RC is also a much better driver than I...lol

Nobody suspects the Marauder. Lots of ridiculous claims of power, but the more I have gotten into this project the more I am convinced that not everything I read on the 'net can be true.
cheers,
Douglas

melloairman
10-05-2013, 10:31 AM
Doug With my PB and its LW choked .251 barrel I have ran a bore ride bullet with good results . The groove is .251 the bore is .249 . at the loading port . The bullet is .249 10 BHN . The choke is .003 for about 3 inches . Bullet bore rides to the choke . Good accuracy and I have good energy as well . With no leading .Marvin
http://i301.photobucket.com/albums/nn55/melloroadman/PB%2025/IMG_7412-PB25CAL6-19-13_zps6556cd26.jpg (http://s301.photobucket.com/user/melloroadman/media/PB%2025/IMG_7412-PB25CAL6-19-13_zps6556cd26.jpg.html)