.25 cal 51 gr. NOE Bob's Boattails

[owen]

I finally got my airgun zeroed at 50 yards, so I decided to shoot a 3-shot group at 121 yards (the extent of my shooting range.) All 3-shots landed in the 1 3/8" red circle and formed a 3/4"-7/8" group. This confirmed at least two things for me. One being that the NOE 51 gr BBT bullets are shooting great through the Airforce Lothar Walther barrel, at the 111-112 fpe level. And two is that my scope's reticle is not tilted (I had to remount the scope with different rings, as I broke the rear ring of my first set.) Again, I'm exceedingly pleased with how well these bullets are shooting for me. Thank you, again, for all those that helped me to get these bullets to shoot like this.

[rsterne]

WOW !!!.... Sub MOA at 121 yards is GREAT !!!.... Thanks for keeping us updated with your success....

Bob

[rkr]

This is getting rather interesting. Could we see some 5 or 10 shot groups at long distance Owen? Is that LW barrel of your's choked?

[K.O.]

unless he changed barrels he sent me the choked part and the length is 16.25" L.W. 1:17.2 twist...

I wanted to be able to post pics of the Trail .25, Mrod .25, And L.W.(Air force) .25 rifling for this thread... so thanks again Owen.

so  here is a quote of where Owens is barrels at...

"
 my barrel length is presently 16.25", 18" Airforce barrel with 1.75" removed (chokeless, now.)
"

 wish I was rich I would pick up a .25 BSA hammer forged barrel  to see if I could make it work... But honestly I would want a CZ ultra lux .22lr barrel to try first...

Me I am pretty happy to see that if you have the fpe and get it out of the barrel right, even with a slower twist they fly very strait... it bodes well for the 30g  .22 BBT as they are very similar... and both evoke  Eley Tenex to me... 

would love to see some 43g and 46g or even just a 45g  .250 BBT as time goes on

not to mention more .22 BBT  on up to about 45 gr...   

I really like it down at .22... because just by putting a 24"-28" barrel on the .25 Mrod platform ( probably have to semi float it) you should have the fpe needed up to about 40-45 grain projectiles...

[rintafile]

I have one friend who tested that bullet on two LW's barrel. One was 12" twist and he didn't get any good results and other was LW's airgun barrel at 16" twist no choked and no good results. But not sure how encompassing test was. I mean did he tested several different shooting pressures etc..

[deadguy]

Things have been crazy busy here for a while, with moving and such, but I was finally able to launch this bullet at s target.  The gun is a Condor SS with the 18" .257 barrel from R&L and Talon Tunes heavy spring and Quick Change Top Hat with no insert. The tank was filled to 3000 psi, and the power wheel set to 2-7.  I have not yet found my chrony in the moving chaos, so I dialed in the power level to where it just penetrates a steel barrel.  I sighted in the scope with a few shots, and the final three are the actual targeted hits.  I was shooting standing with the gun semi-supported (muzzle resting on s trash can) at about 60 yards.  All three shots are inside and inch with two touching!  I can't wait to see what it will do off a bench with a little more practice.

[K.O.]

Wow that is amazing a 253/255 round doing that well out of a 250 bore/257 groove barrel..!   1:14 twist I think

I notice on the R&L site they also state that it is good with 25g JSB Kings..?

[deadguy]

Yes, I did get the .255" diameter mold, but I think the bullets may be dropping from the mold a little bigger than that, as they were impossible to load into the AirForce barrel without using a substantial steel tool, and even in this barrel they still offer some resistance to load, but they will load with finger pressure.

[K.O.]

well the nose being around .253+ gives .0015+ engagment with the lands and the drive band about .0025 engagement... so it is basically bore riding...

But sealing..? it still leaves about .001 till groove contact... now if barrel groove is actually tighter at about .251-252 and the rounds drop a bit big..?

Bob stated that his .250/252  were droping about .0015 large so maybe just enough for the drive band to swage out a bit because of the tall lands...

about how wide are the lands bearing surface..?

The  L.W. and Benji .250 barrels are about .03 wide with ten lands and grooves which gives about a 60/40  groove/land ratio which can help give an idea of how much they will swage the round with their lands (along with their height of course)....

I think that The T.J. barrels are six land/groove so if they are ~.3 wide that gives groove/land ratio of ~ 75/25...

[rkr]

unless he changed barrels he sent me the choked part and the length is 16.25" L.W. 1:17.2 twist...

I wanted to be able to post pics of the Trail .25, Mrod .25, And L.W.(Air force) .25 rifling for this thread... so thanks again Owen.

so  here is a quote of where Owens is barrels at...

"
 my barrel length is presently 16.25", 18" Airforce barrel with 1.75" removed (chokeless, now.)
"

 wish I was rich I would pick up a .25 BSA hammer forged barrel  to see if I could make it work... But honestly I would want a CZ ultra lux .22lr barrel to try first...

Me I am pretty happy to see that if you have the fpe and get it out of the barrel right, even with a slower twist they fly very strait... it bodes well for the 30g  .22 BBT as they are very similar... and both evoke  Eley Tenex to me... 

would love to see some 43g and 46g or even just a 45g  .250 BBT as time goes on

not to mention more .22 BBT  on up to about 45 gr...   

I really like it down at .22... because just by putting a 24"-28" barrel on the .25 Mrod platform ( probably have to semi float it) you should have the fpe needed up to about 40-45 grain projectiles...

I could give them a go in my BSA barrel as Teemu has the mold, although I'm not going to remove the choke. With a choked barrel, how should the bullet be sized? I tapped a pellet to widen it a bit, pushed it through and measured 0.2545. Should I try 0.254 bullets then?

[K.O.]

well I think we need to know more... the barrel is it the ~19" long barrel... and is it about 1:19 twist( it is my impression that is the twist on all the BSA barrels?) # or lands, height and width and aprox fpe you can muster up with Jsb heavy or 40 grain Eun Jin...

will not have to worry as much about harmonics as they are pretty stiff but is the receiver and all up to the fpe..?

I do think these 50 grainers should  be launched  with at least 75-80 fpe is the main prob... at 50 fpe that is only about 670 fps...

It would be like trying to run .22 subsonic in a CZ barrel with its tight bore (about .212) but magnified... they recommend against it... but up around 100 fpe it works...

Scroll down to the question “I’ve heard you use tight bores in your .22s, is that right? What does that mean?”
http://cz-usa.com/support/faq/

Point is you are probably better off with the 40g .250 BBT...

but

hey ya never know it might work...

 in theory I would try to bore ride it as much as it will take and size as little over groove size at the choke as possible...

 and then if that did not work I would size a bit smaller and knurl back up to size... to make it as easy as possible to get thru the choke and it still might not work... even with the 40g .25 BBT...we are in uncharted waters...

scroll down to reply #12,
http://castboolits.gunloads.com/showthread.php?111103-Cast-bullets-for-the-22-Hornet

I will even try paper patching to help get it thru the Mrods choke when I finally get going if I can not make it work any other way...

My back up plan is also ~ 1:19 twist (but unchoked) which suits the 40g .25 BBT better than the 50 grain...

[rkr]

well I think we need to know more... the barrel is it the ~19" long barrel... and is it about 1:19 twist( it is my impression that is the twist on all the BSA barrels?) # or lands, height and width and aprox fpe you can muster up with Jsb heavy or 40 grain Eun Jin...

will not have to worry as much about harmonics as they are pretty stiff but is the receiver and all up to the fpe..?

I do think these 50 grainers should  be launched  with at least 75-80 fpe is the main prob... at 50 fpe that is only about 670 fps...

It would be like trying to run .22 subsonic in a CZ barrel with its tight bore (about .212) but magnified... they recommend against it... but up around 100 fpe it works...

Scroll down to the question “I’ve heard you use tight bores in your .22s, is that right? What does that mean?”
http://cz-usa.com/support/faq/

Point is you are probably better off with the 40g .250 BBT...

but

hey ya never know it might work...

 in theory I would try to bore ride it as much as it will take and size as little over groove size at the choke as possible...

 and then if that did not work I would size a bit smaller and knurl back up to size... to make it as easy as possible to get thru the choke and it still might not work... even with the 40g .25 BBT...we are in uncharted waters...

scroll down to reply #12,
http://castboolits.gunloads.com/showthread.php?111103-Cast-bullets-for-the-22-Hornet

I will even try paper patching to help get it thru the Mrods choke when I finally get going if I can not make it work any other way...

My back up plan is also ~ 1:19 twist (but unchoked) which suits the 40g .25 BBT better than the 50 grain...

18.5" barrel. Twist rate about 17-18:1 (measured half turn), 6.46mm bore at choke and I'd guess around 6.35mm (0.1mm accuracy, could be 6.30 just as well) lands. I'm throwing 34 grainers at 890 fps so I hope these 51 grainers would fly around 750 fps as the barrel length is limiting power. If they are accurate with the barrel I could do some mods later and probably reach around 800 fps.

The barrel is pretty loose with JSBs up to choke so I'd guess bullets could be bore riding up until then. However, what happens at the choke is then another matter. There's bound to be some lead expanding to the grooves so as 6.46mm = 0.2543" I'd be tempted to try 0.254 die for perfect sizing. Of course I could try 0.255 as well but that would then be 6.477mm which seems a bit too tight.

[Hobbyman2007]

I cast my first batch of two hundred yesterday , unfortunately they won't chamber. They drop as cast at .256 to .257 according to my cheap mic. These were for the .254 /.255 mold. Guess I'll have to wait for my sizer to come in . They look great for first time casting , was a lot easier than I originally thought.

[stealthhunt]

looks like they will hit hard! I always into heavy pellets. what will you use these pellets for like for hunting small games?

[Hobbyman2007]

Well I forgot , I had bought a couple dies and a lee press a while back. Sized to .254 and they are chambering just fine . Here's a quick string through the Hatsan BT65.
893
895
893
897
897
895
883
879
Start fill at 2900 , end at 2250 . That's averaging 90 fpe for 9 shots . Now for accuracy testing .

[Hobbyman2007]

Here are my findings . I sized the solids to .254" and the hollow points to .2545 " . The solids shot a lot better 1" at 50 yards vs 3" at the same distance both at 900 fps .When I cast these ( first timer ) I used a 25:1 ratio of lead tin mix . I think they may be a bit too hard . The good news is that they are shooting pretty well . I'll keep working at it hopefully post some pics of my groups next time out .

[K.O.]

I got to thinking about when Owen ran these loose and was getting good accuracy but they leaded up quickly.

Nick initially got good accuracy even at lower velocity/slower twist and then they lost accuracy pretty quickly(probably leaded up the choke?)

and then they show signs of doin' well  in  Tom's  .257 barrel and have to be a bit loose in it...

and I am worried about leading the choke  on my Mrod when the 40g molds get made...

So I got to thinking I just may copper plate  them to see if that will help prevent it... all you need is some root killer(copper sulfate) from the hardware store, copper wire, water and some d batteries... Heck been thinking of trying it on some pellets for a while since even Crosman is putting some out now...

so my point is if they star tout well in your barrel and then loose accuracy and you find leading... the prob might be fixed with copper plating...

Somewhere in my junk I have a low amp power supply and a collection of wall warts...

[Hobbyman2007]

Here are a couple pics of shooting at 80 yards. The first two are with the solids ,and the third is with the HP's. Not my best shooting but acceptable for hand cast bullets . None of which were perfect I might add , I'm still learning how to cast right now .

[K.O.]

can not see well enough are those rips or yawing bullets in the pics?

I for practice, have been pouring some Bator 225-55-rf  and the new 225-55-rf... the big sprue hole(~.140) is causing some slight base distortion... I think about .125 would be about right... I have been slow and opening with an old hammer handle... next session  will try right after flash and shrink... with a gloved hand... I wonder if lee sells blank sprue plates. They do sell blank Molds guess I will have to contact them and find out...

being sloppy with big sprue puddles on the plate seems to help fill out. No probs with sicking until the Bator mold got real hot I slowed a bit and they stopped sticking...had to tap the handles with the hammer handle till it cooled just a touch...

lots of little thing to figure out... I see it as a fun challenge in problem solving for each round/barrel/powerplant and that is after getting the mold/pour right...


 I am hoping in the long term to use the Lee molds to make  a few ( different .22 rounds by decking them (pics below).

 So the Bator full size @ ~50g...

 Decked to the back of the rear band removing the gas check comes out a flat base about @ ~44g...

decked to the front of the rear band comes out to a heeled round about ~36g...

and decked to the back of the front band comes out a flat base about ~31g (if it can be decked that far)
 
 then with the new 225-55-rf

Full size is About 55g

decked to the back of the rear band gives a flat base round ~48g...

decked to the front of the rear band gives a heeled round ~41g...

decked to the rear of the front band gives a flat base and ~35g...  once again if it can be decked that far...


I was a bit lazy with how measuring much solder(60/40) with the melt I think its about 4-5%Sn and .5 sb (from  the crosman pells) because it was recycled pellets of many makers...still have more did not even have to add the bit of plumbers lead I found in my neighbors yard.

have a couple sizing die  ~.2238 and ~.2244 so sized a couple and then did push thru thru a old seasoned model 60 .22 lr barrel and and new unfired 883n .22 WMR barrel...

at .22 the base distortion just might be sized out to a great extent... the .224 (WMR)barrel does not engage the gas check so it still matters with it for sure...

Along with the 40g  .25 BBT and the 30g .217 and .220 BBT to figure out and experiment with... it looks like a couple years of fun learning and hopefully mastering small bore cast with air power...

So yep I am casting for a rifle I do not have yet..   But the first step is making the best cast possible and I need to practice and develop a routine techniques and such so I am remelting about twice a week... with the tiny lee pot and a Lyman ladle.. ...

I have cast Aluminum as a job and watched boolit casting and have the eye net to help so have a good bit of confidence I will get there...


well any ways if the pics were a bit better might be able to read the targets a bit... distorted bases  and other casting flaws can show up as yaw even lead to instability... So yep good fill out on the bands/base no voids and wrinkles etc...

I was pretty amazed that towards the end of the first casting session they were dropping very well... I figured it might take some cycles to heat and cool before that would happen...

all I did for mold prep was to wash with dawn and let dry and then some sprue lube...

[K.O.]

If you still have the full size pics if you want email them to me and I can crop and size with windows paint to maybe get better detail...