Q:

A 257 Cast Bullet Reference Guide

Hello Gents and Gals,

PURPOSE:
This page is a page that is dedicated to the .257 caliber Air Gun (s). Call it a Dedication Page, or call it a Reference Page or call it a Info Page, it’s all of the above. This page will stay updated with “CURRENT” info and will contain info on the guns that are available in 257. And that’s the point of the page, to share information regarding the 257 caliber Air gun and to become a quick reference page for anything that has anything to do with the .257″. This will be a page that can be found quickly and will contain all “CURRENT” info on the 257. That means MORE work for me and LESS work for you.

HISTORY:
The 257 caliber powder burner cartridge has been around since about the 1920’s. But in air guns, a 257 caliber powder burner barrel liner from TJ Enterprises has only been recently installed on a current air gun. As far as we know, Jack Haley and John Bowman are the 1st creators of such said air gun/caliber combos. And this gun is the Jack Haley .257 Scandalous which won L.A.S.S.O. in 2012 on its maiden voyage in the hands of John Bowman. L.A.S.S.O. is short for “Longrange Airgun Silhouette Shooters Organization” and it is simply and event for Air Guns only and steel targets are set up out to 300 yards. The 257 Scandalous quickly gained notoriety for what it was capable of. And that is……Long Range Accuracy and power. John Bowman would also often dispatch coyotes at well over 300 yards. John Bowman has shot 10’s of thousand’s of cast bullets in the 257 Air Gun and has openly shared all that he has learned. We owe much of what we know about the 257 today to Jack and John. The Haley Scandalous 257 is a very powerful, accurate and traditional Air Gun. Web links and pictures below.

CURRENT:
Doug Noble is an avid air gunner and an excellent machinist. Today, Doug is transforming the Airforce line of guns into 257 caliber beast. Doug has a history of machining since his early High School days and his current work on the Air Force line of guns is exceptional. His many post and pictures can be viewed right here on this very forum. Air force Air Guns have been around since 1994 and currently manufacture about 6 types of air guns. Air Force air guns are not very traditional looking and might remind you of an AR-15 type gun. No traditional wood and steel and bolt handle on these…lol! The Air force gun massaged over by Doug is one powerful and accurate “NON TRADITIONAL” rig. Web links and pictures below.
Also, .257 Airforce airguns can be bought from Randy at RandL Airguns (http://www.rlairgunsupply.com/).

CALIBER:
The .257 by nature is a small game to medium game caliber. In powder burner format such as the 257 Roberts or Weatherby…etc…etc…etc, it can take Deer/Antelope sized game at some decent hunting distances depending on bullet construction/manufacturer. But in an air gun, we stick mostly to Coyote sized game at the biggest. Its one of the best small/medium game calibers IMHO. Bullets will range from about 60+ grs up to roughly 120 grs. Nominal O.D. of bullets will depend largely on groove diameter of ones barrel on his/her gun. But sizes will run between .257-.258″ as somewhat of a norm. But again, sizes can be up to about .260″+. The B.C. or Ballistic Coefficient of many available bullets will range from .129+- up to roughly over .300 BC. And in comparison to the typical .251 caliber Diablo Pellet such as JSB, Bejamin or Beeman (H&N), which has a BC of about .030+-, the lightest .257 bullet will have roughly 4x’s more BC. So as you can see, the 257 in an air gun pushing 900-1130 fps can do some amazing distance shooting and retain a lot of energy. I MEAN……..FOR AN AIRGUN AND ALL………………….LOL!

PICTURES:
Here are various pictures of some current 257 caliber air guns


John Bowman and his 257 Haley Scandalous. Winner at L.A.S.S.O. 2012



Cedric aka Tofazfou shooting his Doug Noble TalonDor 257 Cal.


Doug shooting his custom/self built Condor 257


Joe Grits 257 Condor by Doug


RJ Porter’s Haley 257 Scandalous



RoachCreek’s Haley 257 Scandalous

.257 BULLET MOLDS (manufacturers):
RCBS MOLDS – http://www.rcbs.com/
LYMAN (IDEAL) MOLDS – http://www.lymanproducts.com/lyman/home/
NOE MOLDS – http://noebulletmolds.com/NV/index.php?osCsid=j7u9gieqlre78413k41t63lb31
HOCH MOLDS- http://hochmoulds.com/index-1.htm
LBT MOLDS (custom molds available) – http://lbtmoulds.com/index.shtml
ARSENAL MOLDS – http://arsenalmolds.com/

BULLET CASTING EQUIPMENT:
BCE can be bought from a multitude of websites and or stores. I refuse to list any in particular cause individual results might vary. But places like MIDWAY USA is a decent place to start if you want to get into casting. Bullet casting is NOT for everyone and its time consuming. At the same time, like reloading, it’s very rewarding. It also does not take a lot of equipment to get started. Here is a list of what’s needed to start casting for the 257 (or ANY caliber):
1. Safety Goggles or Glasses or even a Face Shield
2. Long sleeve Denim shirt
3. Brushed Leather Gloves
4. Long pants in either Denim or another NON FLAMMABLE material
5. 257 Bullet Mold
6. Plenty of lead
7. LYMAN, LEE or RCBS melting pot (20 lbs is a good). You can use a propane burner with some type of cast iron pot also. But that’s up to you. Do your homework.
8. Dipper/Ladle
9. Either a reloading press or a LEE hand press that will accept a standard 7/8×14 TPI sizer die
10. Bullet Lube and some studying/advise and some Common sense

Many of these molds can be found at a multitude of websites. Here is one such example: http://www.justbulletmolds.com/. Since there is always more than one website for any particular product, I will leave the shopping and goggling up to the buyer/reader who wants to shop for the lowest price on product and shipping. The web links posted up above for molds is just a guideline and not the single BEST website for said product.

PICTURES OF VARIOUS MOLDS IN .257

Doug’s 77 gr FP LBT mold


Roachcreek’s 100 gr NOE FP Mold


Tofazfou’s 74 gr FP LYMAN 257420 Mold with custom HP Pin by ERIC at HP MOLD SERVICES


Tofazfou’s 80 gr NOE FP Mold


Lyman 257 Mold



Arsenal 257420 Mold

VARIOUS .257 BULLETS:

LYMAN 257420 bullets cast by Tofazfou. FP and HP


IDEAL 100 gr HP Spitzer cast by RJ Porter


HOCH 109 gr FP’s in 20-1 lead/tin cast by Roachcreek


Various bullets cast by Tofazfou, RJ Porter and Hunters Supply


NOE 100 gr FP’s in 20-1 lead/tin cast by Roachcreek


NOE 78.3 gr HP vs 83.5 gr FP


Lyman 257420 vs NOE 80 gr

VARIOUS CAST BULLET BC #’s:
LYMAN 67 gr LFN GC 257420 = .129
LYMAN 89 gr LRN LOV GC 257464 = .204
LYMAN 89 gr LFN GC 257312 = .208
LYMAN 98 gr LSP GC 257418 = .221
LYMAN 113 gr LRN GC 257325 = .235
RCBS 117gr SP GC 257-120-SP = .271

Here is a PROCEDURE on “FIRE LAPPING” your airguns barrel submitted by Roach Creek:

Fire lapping a barrel.

I have fire lapped several rifles in my shooting career, most of them center fires that used jacketed bullets and I did it for improved accuracy, the 257 bore air guns I did for a different reason.

I fire lapped my two TJ Barrels for my Haley because I wanted them to be smoother inside to allow more shots between cleaning and for easier cleaning once fouled. Before fire lapping I was getting around 20 shots before I had considerable streaking and accuracy degradation, now it around 45 shots.

When I cleaned I used fine bronze wool on a 25 caliber brush and then followed it up with several doubled patches on a jag, then followed by #10 weight silicone oil to prep the barrel for the first shot lubed with #10 silicone oil. After fire lapping all but the most stubborn transfer deposits are removed with double patches.

The 1-14 barrel, I fire lapped with a Wheeler engineering kit from Midway, I had used their kits before and they had worked, so I was comfortable sending abrasive coated bullets down my bore, yes that does sound drastic, which is why I wanted to go with a proven, to me kit.

I prefer fire lapping to hand lapping due to the fact I ruined a Mini 14 barrel in my misspent youth and have never revisited hand lapping since.

The kit comes with three grits in little jars, 220. 320 and 600. Also included are two 1 inch by 2 inch steel plates and very clear instructions.

On my 1-14 barrel I followed the instructions on the kit, but used 15 shots per grit instead of the recommended 20 , 220. 320 and 600 and I cleaned thoroughly each 5 shots and thoroughly between grits. In the end I had a very smooth bore that resists fouling and cleans easier once it needs cleaning.

Then I fire lapped my 1-10 twist barrel and things were different.

First of all I did not use the 220 grit and I checked between shots because I was not using lube on the bullets as before so I was interested to see if they were fouling without lube because I had not checked that before on the 1-14.

And indeed they were, if I fired one shot, I could not notice fouling, on the 2nd shot I did notice fouling and on the 3rd shot I had major streaks. As a result I fired 20 shots of 320, cleaning thoroughly between shots, which is one hell of a lot of work, and then after those 20 shots I switched to 600 grit and I fired 25 shots, cleaning each time between shots.

To me the cleaning between shots was a no brainer. If I have streaking, I am polishing the lead deposited in the bore, not the bore.

When I shot the rifle after cleaning I also noticed again something different, the accuracy with100 grain NOE bullets had noticeably improved, and of course the shot count between cleaning had also.

I had miked my groove diameter prior to fire lapping and could not notice a difference in pre and prior lapping, but I was also using my “Harbor Freight caliper for the blind” so it was hard to tell if anything had changed in dimensions. Doug slugged the barrel when I had it set back for recutting the lead, it slugged out within the norms of other TJ barrels, just one heck of a lot smoother.

I did this on the 1-10 after I had cut the lead for 100 grain NOE bullets, I did not notice a increase in the lead dimensions or that they chamber any easier, they are still in that “putting a cork in a wine bottle category”.

I fully recommend the Wheeler engineering fire lap kit, but I would recommend cleaning every shot and not using the 220 grit.

Regards,

Roachcreek

VARIOUS RECOMMENDATIONS:

Cast bullet supplier that I recommend:
RJ PORTER – http://www.accuratebigboreairgunammo.webs.com/

Jack Haley Airguns (please read his webpage): ******MR HALEY PASSED AND THE WEBSITE NO LONGER EXIST – I CHOOSE TO KEEP IT UP******
http://www.southernairgunconversion.com/

CUSTOM 257 Air Force Condors: ******DOUG NO LONGER MAKES CUSTOM CONDORS******
Doug @ dyotat100@aol.com

For Hollow Pointing any bullet mold contact Eric at:
http://www.hollowpointmold.com/

.257 Barrels by TJ Enterprises

101 “QUICK TIPS/FACTS” about the 257

1. Best bang for your buck barrel in .257 is the TJ Enterprises barrel liner (Google this company name for pricing and phone number. No internet sales)
2. Common bore and groove dimensions are .250 BORE/.257 GROOVE
3. Common O.D. dimensions of TJ barrels tend to be roughly 9/16″ (.562″+-)
4. Pure Lead or 20-1 Lead seems to be the best to date
5. Hard Cast bullets don’t appear to be as accurate as Pure Lead in TJ’s barrel liners. But don’t discount harder cast bullets. These are firearm barrels.
6. Fire Lapping or Hand Lapping both work wonders in these barrels and are pretty much necessary to keep leading down and accuracy up
7. The more these barrels are shot, the more accurate they get
8. So far, accuracy is superb at velocities from 900 to about 1130 fps. More data to come. Please test velocity for your particular guns best accuracy
9. Various Air Guns and Barrel Manufacturers could be used for this project. The list is still growing.
10. To date, both the Condor and the Haley 257’s have hit Soda cans at 446, 502 and 552 yards!

IMO: Guns that DO and DON’T make for good 257 conversions
DOES – Jack Haley air guns (particularly the ones that fill to over 3600 psi)
DOES – DAQ air guns
DOES – Daystate Air Rangers (especially the 80 FPE version)
DOES – Daystate Wolverine 303 (expensive gun)
DOES – Big Bore EXTREME air guns
DOES – Korean Big Bore air guns (Shing Sun Career, Sumatra’s, Dragon Claws andSam Yang’s. And even the EVANIX 9mm guns)
DOES – XP Big Bore air guns including the Corsair
DOES – Air Force Condors
DOES – OF COURSE ANY CUSTOM BUILT or HIGHLY TUNED AIRGUN SUITED FOR MAKING SUCH POWER

DOES NOT – CALIBER CRICKETS (lol)
DOES NOT – EDGUNS
DOES NOT – FX BOSS 30 cal (too much restrictions within the guns internals)
DOES NOT – TOO MANY TO LIST HONESTLY (small bore air guns in general are not good for this conversion due to either TUBE size volume or internals that lack the ability to be highly modified. Many SB air guns are made for consistency while making 12-50 FPE of power and not 130-200 FPE)

***DISCLAIMER*** Due to a lack of knowledge on every single gun made today and also the machinist in existence and their capabilities, the above opinions are due to available current info and even the LACK OF. The sport is growing and the amount of people that are getting into 257 cal airgunning is steadily/slightly growing. So information is CREEPING in at a snails pace. But as more info comes out, the above listed info MIGHT change.

Game taken with the .257 cal.:




CUSTOM PARTS SECTION:
All parts by ADAM VIGIL (http://talonairgun.com/forum/viewtopic.php?f=12&t=9980):



http://www.maddogriflestocks.com/





MD stock on my TD257

Other Guns

All Replies

Viewing 15 replies - 331 through 345 (of 363 total)

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Wow!! 53 grainers now.

I went stupid yesterday, and milled the gas check area off of my 257420 mold. 😯

In fact, I removed just a bit of the last driving band as well.

Results, well, my spring that Doug sent with the bbl. had lost a bit of its mojo, and the velocity had dropped from 930’s to 903-4 fps on the first shot. The new (Custom 😆 ) 240 droped the weight from the 20-1 as cast at 72.2 to 53.6 gr. and the velocity settled in at 1009 first shot.

Yep, I lost a bit of BC, but the velocity is actually showing a bit less drop. So On to testing.

First 5 shots sucked. 😳 So I ran a bronze brush thru in and an fp-10 soaked patch thru it, and a few dry patches and it got worse. 😆

Well, after 5 or shots it started comming around. Filled to 3200 psi and it put the first two through the same hole widened horizontally. The next two also printed side by side, even tighter, but about 1/2″ to the left. (Wind was blowing like hell.) (These were at 80 yards.) I then re-filled to see what a shot string would do and 10 bullets printed a group just over 1″, with the last shot droping about 3/4″

This was better than with the heavier bullets, as 5 shots was really stretching it at 80 yards with my small tank. The lighter bullet seem to have stretched the shot string out a good bit. Almost doubleing the shot count.

The down side, is that the lighter bullet is a little more effected by the wind.

Cant wait to see what OldGoat comes up with this weekend, as he is doing the same to both the 257420 as well as the 80 gr NOE. Should be interesting! 😀

KnifeMaker

Thanx Adam and everyone else who reads this page.

BTW! Its still growing and changing. lots of needed info to still add to this page. Including RC’s new WORLD RECORD 😎

UH-HU! And when he does, you gonna make me a deal on that 80 Gr NOE??? Right___ 😀

Knife

Doug,

Mostly I just hold the two slugs up against the sky and squint with my one good eye. 😛

I was hoping you would say your going to sell me that Ideal spritzer mold.

RC

To really measure slugs you need to use a mic. Sorry Charlie.

Calipers only measure in .0005″ increments. I have $200 calipers and they are only guaranteed +- .001″. So with only being that accurate and reading .0005″ you could be off .001″ easily.

I only measure with calipers for a rough idea of size.

My mic’s measure to .00005″ and accurate to .00005″

If anybody wants to slug there barrel and send me the slugs I will measure them for you.

4 cavity molds, sizers and muzzle breaks.

I get a lot of PMG’s one these subjects.

80 has answered the muzzle break question, but I might add that two days ago at 640 yards I shot the 80 and 100 grain NOE with and without the muzzle break and with and without the rubber bulb on my barrel. I could see no difference in the group size in the impact with the mine tailing and the dust from the hits, which is a very crude test, so the next month or two I will be experimenting with both and 10 shot groups with the 420 HP and NOE 80 grain and both barrel twists at 280 yards.

I do notice a difference in my sound box as a muzzle break disfuses the air better and allows it to be absorbed better, but I don’t know of anyone who uses one and my sound box is sitting unused these days as everyone shoots far louder guns around where I live.

4 cavity molds: I use them because I shoot a huge amount of bullets. However they are far harder to get consistent, + or – on tenth of a grain and to get sharp bases with. Read that difficult to cast good bullets with for me with 40 years of doing this and I would rather have two 2 cavity molds instead. If your shooting IPSC or your making bullets for sale like RJ, it is a completely different matter, but with a air rifle that needs refilled every 2 to 10 shots you don’t need bullets by the pound per minute rate and the 4 cavity molds will be very frustrating.

Now about 6 cavity molds…………… never again!

Aluminum mold damage easily but do have some advantages, but I prefer steel two cavity molds and running two of them at the same time gives me far more consistent bullets and at the end of the day after sorting and weighing I have just as many or more than if I was running a single 4 cavity aluminum mold.

NOE does sell two cavity aluminum molds and and there 80 grain bullets are about as accurate as anything I have shot to 280 yards. However a 2 cavity 257420 Lyman mold is just about as good as it gets with a 257 air gun, especially if Erik has hollowpointed it, and for a Condor set up perhaps ideal for the weight and the velocity your going to be shooting. The Lyman 257420 is a simple and extremely effective answer to what mold should I get.

You can shoot your bullets unsized quite well. Best performance is being .0005 to .001 over your slugged barrels groove diameter, but you need to slug that barrel first, and I can’t say that enough.

You need to have a 4 position dial caliper to do this right, but a three position one will do for mere comparison, but is a crude way to do it. I get by very well with a ,258 Lee sizer, and Lee is the only one you want to use, the RCBS and LYMAN sizers and press are for PB bullets and not air gun bullets and require a special and expensive press/lube pump combination such as the Lyman 450 to use them.

Right now Lee is behind on custom orders and the 258 sizer is a custom order, they cost 35 bucks and a portable Lee press is 35 bucks. You want that sizer to be slightly larger as I said, but you can open it up with a 25 caliber bronze brush chucked up in a drillmotor, the brush needs to be wrapped in fine steel or bronze wool and saturated with 600 grit grinding paste. Go slow and again have a 4 position caliper to check your progress.

I hope this explains things better for the new guys getting into this.

RC

Charlie (RC) got one for 110.00 from brownells but he had to get it in .30 cal (a little too big). He also has this sexy one from NorthWestPrecision. I talked with them and the weight of the 0.850 is 3.5oz and the 0.950 is 4oz and that is prior to receiving bore hole so they will decrease in weight somewhat. They will drill any bore size you want (.270 for the .257) Here is the link on fleabay:

http://www.ebay.com/itm/Muzzle-Brake-Rifle-or-Pistol-Muzzle-break-caliber-drilled-to-what-you-need-/221200510627?pt=LH_DefaultDomain_0&hash=item338093eea3

Great Thread Cedric.

Really good addition to the forum

Thanks

Caboose,

I don’t think very many folks have tried very many muzzle brakes as of today. the 257 is still in its infant stages and not that many people own them. YET! But I use a HATSAN AIRSTRIPPER and I love it. It works for sure. I got the air stripper from Pyramid Air. RC uses a muzzle brake so you might wanna see which one he uses.

Having exelent results with the 257420 today. At 80 yards, first two shots, same hole. Only very slightly wider when looking really close. Third shot, touching to the left. And No Fliers Today!!! :8:

Here’s a question- if I wanted to go unshrouded, what muzzle brake that’s been used gives the best recoil control and accuracy? I know someone was trying a few out… and also- this .257 im building is a dedicated gun- what length barrel should I go with, since I’m not going to shroud it? looking for accuracy. I’m going to hook it up to a 90cu in 4500 psi tank. and how is everyone’s gun shooting? I mean, how many cc’s of air is each shot in a modified condor? If these questions belong in another section, I apologize.

Gotcha Ced- That was my fault 😥

GUYS,

I can appreciate all the interest in the 257. It’s worth it.

But this page is not the place. Its just a info page and all replys back and forth should have a separate thread.

THANX GUYS!

Cedric

I feel the same way Ced… and I’m not a machinist! Though I wish I were- I’m just an idea man. But I do want to make this happen!! I’m also looking at an Eliseo tube gun type build- check out the photos below:


I think you’re on the right track with the thicker tube… So thick in fact, that maybe the trigger group could be attached like real steel bolt rifles, or like this Eliseo rifle, with screws… Here’s another trigger group picture:


This might be the way to go!!


Here’s a shot of the complete rifle… Of course, there’s no stock but the tanks back there, and I’d be using Tony’s tank adapter. This is going to be fun!

Viewing 15 replies - 331 through 345 (of 363 total)

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