Gamo Urban with 30gr BBTs

[EdinGa]

My Urban was down for awhile with a bad magazine, and life has been keeping me fully occupied, but I'm finally back with another post. Lee's excellent magazine is running flawlessly with the cast bullets. This is just a fun video of the smack these things put on my rimfire spinners at 35 yards. Muzzle velocity is around 640 fps.   

[Wayne52]

Eddie I've shot those same slugs from my Airmax Dominator doing 900fps in the past and they're devastating.  Eventually I'd like to buy the hollow point version mold when NOE makes some more.

[Hobbyman2007]

Great little bullet. Like Wayne I’m waiting for the HP version to be made . Most of my .22 cal guns shoot these well . Good shooting by the way .

[EdinGa]

Eddie I've shot those same slugs from my Airmax Dominator doing 900fps in the past and they're devastating.  Eventually I'd like to buy the hollow point version mold when NOE makes some more.

I'd love to have the hollow-point too. I wonder if NOE is planning another run?

[EdinGa]

Great little bullet. Like Wayne I’m waiting for the HP version to be made . Most of my .22 cal guns shoot these well . Good shooting by the way .

I've entertained the idea of making a jig turn these into hollow-points, but they shoot so well that I haven't done it yet. That big meplat really hits hard like it is.

[Wayne52]

Eddie I've shot those same slugs from my Airmax Dominator doing 900fps in the past and they're devastating.  Eventually I'd like to buy the hollow point version mold when NOE makes some more.

I'd love to have the hollow-point too. I wonder if NOE is planning another run?

I joined the NOE forums a while back because there's some neat stuff in there, of course it's no where near as busy as this forum but they mainly build the quality molds for all kinds of PB's and airguns. There's a thread on there specifically for members and guest's to make comments and an inventory forum with a child board "What Would You Like to See Run"

http://www.noebulletmoulds.com/smf/index.php

[EdinGa]

[/quote]I joined the NOE forums a while back because there's some neat stuff in there, of course it's no where near as busy as this forum but they mainly build the quality molds for all kinds of PB's and airguns. There's a thread on there specifically for members and guest's to make comments and an inventory forum with a child board "What Would You Like to See Run"

http://www.noebulletmoulds.com/smf/index.php
[/quote]

Thanks! I'll check it out.

[K.O.]

Hi Ed glad to see ya back... Have a .22 Buccaneer now is sorta your fault.. after seeing how the BBT did out of your Urban could not resist...just had been wanting one for to long...Also have an Urban and At44 Long .22 now... but those were just unbelievable deals that I could not pass up...$219 for the At44(Hatsan Clearance) and the Urban was an Amazon sale $199 plus I had a 25% off offer...

Got my best 60-65 yard pellet group the other day and at the same time almost pulled of a really great BBT 30g group... got a rock Jr rest and was prone on a blanket... Right before that did an un-lubed 40 yard group... just to check... am using trident divers silicone on foam in a used JSB tin...

I am still at stock as received with all three rifles Urban 620 fps Buccaneer 675 fps and AT44 795 fps...
so first below is the un-lubed group then the 60 yard groups(5 shot)... then some mostly typical of 35-40 yard side rested groups... I am pretty sure I can do better... think MOA is very possable, will explain in next post... oh under the quarter is a sub .75 oto group from the Urban...they are 5 shot groups also...

[K.O.]

Ed could you do the thumbnail test on your rounds... I asume you are still using the SASS range scrap..? That way we will know wether you are above or below 12 bhn...

So here is why...

in the below thread reply #10 was using about 4-5% tin and trace antimony to cast the BBT @ about 780*in the pot... those were pretty representative of groups with that alloy...spread out but solid .75 ish groups.... and my recovered slugs looked pretty much like yours... nicely engraved head and tail( but not quite as deeply)...

https://www.gatewaytoairguns.org/GTA/index.php?topic=151471.0

If you notice the above groups (this thread) they are grouping more tightly but with fliers out to about .75"... they are softer cast...about 1.5% tin @ 740* in the pot...The below pic is of recovered 1.5% tin slugs from the Buc(left) and urban(right)... notice the nose is barely engraved... on the Urban it is all the way round on the Buc it is on one side only... My .217 sizing die does not size the nose(did with the 4% tin mix)... they are just under .217 and I mean just a smidge... .0001-.0002 ish smidge...

So I do think the softer rounds do make it thru the choke better... I also think My Buc has a very very slightly looser choke... so will be trying My .220/.222 Mold... will get another insert to open a bit to size to .217 and a smidgen(.2173-.2175)... the Buc did not like .217 and Knurled... will check the Urban but expect about the same...

the Buc and Urban consistently seem to react in very close to the same Manner...  the 7 ish fpe difference and longer Barrel of the Buc does not seem to make a lot of difference in 35 yard accuracy... 

So yeah I think the heads are under size just enough to cause the fliers with the 1.5% tin mix with the .217/.219 mold... Wish me luck am very hopeful of very near MOA if I get everything right...

Oh also I did not weight sort and did a very loose visual sort... a more rigorous sort might improve things some also...

[K.O.]

Oh here are some more clues about why they act the way they do in my rifles... notice that Both the Buc and the Urban like sized to .217 and .219

but not sized to .218... and it is slightly more evident  with the Buc...

Not shown is .216 and .216 Knurled... that bad..   these groups I made to share to help  illustrate why I think the noses are undersize and may get better with the .220/.222...

at .219 the back of the round is held firmly and the slightly loose bore riding nose is not such a big deal... at .218 as it goes down the barrel the back end of the round is not touching the groove firmly which causes the nose to wiggle more...and hit the choke slightly differently every shot...thus not coming out the barrel the same... not real bad because of the rounded nose does some centering... but being under size well has room to cant some...

so why do the same under size noses do better at .217... well because with the back end being smaller it does not hit the choke as hard and the nose stays centered better...

That is my theory anyways... will listen to others... but the behavior of .219 and .217 working better than .218 was consistent...

  ?

[EdinGa]

Ed could you do the thumbnail test on your rounds... I asume you are still using the SASS range scrap..? That way we will know wether you are above or below 12 bhn...

I'm at work now, but I will be glad to do a thumbnail test and take some pics when I get home. In the meantime, here's a couple of 60 yard groups for you. The bottom one only has 4 shots because the 3rd shot hit a limb on the way down and I was getting close to the bottom of my sweet spot so I didn't shoot a 6th shot.

[Insanity]

Tuning in as I would like to eventually tune my urban to shoot slugs for hunting.

[EdinGa]

Tuning in as I would like to eventually tune my urban to shoot slugs for hunting.

My hammer spring tension is at 13.5 turns and I'm getting about 10 to 12 shots in the sweet spot that are suitable for longer ranges. It's good for 20 shots at 25 to 30 yards.

[Insanity]

Tuning in as I would like to eventually tune my urban to shoot slugs for hunting.

My hammer spring tension is at 13.5 turns and I'm getting about 10 to 12 shots in the sweet spot that are suitable for longer ranges. It's good for 20 shots at 25 to 30 yards.

Thanks  need to get a crony and do some tuning now.

[K.O.]

I need to mod my Buc and Urban to make it easy to adjust hammer spring tension(just a matter of drilling a hole in end cap)... then re find the sweet spot after I turn it up...right now tho the 15g JSB are so good I have not... would like being able to send both cast and them at moa..

But yep in some rifles have read as little as a 10 fps difference has made a large difference in accuracy (well with pellets any ways)... do think there are some slight harmonics going on with the Buc and Urban... but not as bad as the longer 23" barrel of the Hatsan... I imagine the 15" (urban) and 19"(Buc) barrels being hammer forged helps a lot also... they are just smidge larger O.D. also... I do still have the barrel bands on my Buc and Urban which may be another factor... My older Buc .177 had a different barrel band... was metal and only contacted the barrel at it's top pulling down slightly...so I will try removing the barrel bands soon also... It does look like you are doing a bit better with the harder cast rounds than I am... maybe it is partially due to the band tying the barrel down and so tying it to the harmonics of the rifle as a whole more..?

So yep have some things to try still... 

Things do seem pretty consistent between our rifles... and all would get  us a rabbit dinner at 60 yards with the BBT...  Thanks for sharing your result again it does feel good to prove you do not need a ton of fpe to make slugs practical... you do need to know a bit more and be skilled at range estimation past about 40 yards at 30fpe and below with the 30g round... but as is right now our fore fathers would have loved to have any of our three rifles for small game rifles...getting accuracy with a .32 Tennessee Squirrel rifle was not easy and almost impossible past about 30 yards is what I have heard all my life...some said 10-15 yards...  the Biggest thing I like tho is if I wanted would not have to buy pellets ever again.. love that feeling of independence...



Man I wish Money grew on trees... PA sale has the Urban back down at $239 for a day or two...need a couple more..

[K.O.]

If Al comes out and says he can/will do these molds with RG pins for the hollowpoint I will be in for .22/.222 immediately... I just do not like the single lyman... Have it with the 223-39-rn... but some have reported better accuracy with the hollowpoints...

Wish the op of this thread was still active wondering how he was doing and how he was doing it more...  Might get some clues for my At...

https://www.gatewaytoairguns.org/GTA/index.php?topic=141114.0 

The .217/219 BBT well was able to get it about .75" at 35 yards with the AT... tried sized and sized+knurled from .219 down to .215... .216 and knurled is the only thing that worked at all...  captured a couple of the sized .219 and they had rifling marks down one side of the body(which is .2125) that tells me it is coming out one side of the barrel... it definitely seems it needs the  .2145 body of the .22/.222 mold...

loving the fun of trying to read what they want tis like learning tracking al over again...  post #5 shows a 3 shot group below link... five shots are about the same and a few smaller...

The way it sends the 28g Eun Jin says I have a decent chance of getting better with the BBT also imo... I do think sizing to .0005 rather than .001 may be important with it... heck that may be the case with any choked barrel..  

https://www.gatewaytoairguns.org/GTA/index.php?topic=158191.msg155753762#msg155753762 

anyways Having a blast Thanks for the inspiration... really wanted the .22 Buc but needed the little push your thread provided...

edited with better pic...

[Wayne52]

My mold came in the mail today, it's one heck of a lot heavier than the aluminum mold that I've already got for these slugs.  A 2 or 3 cavity would have been much nicer for ladle pouring but I figured I'd take what I could get because I've wanted a hollowpoint mold for quite a while now.  I think this is the heaviest mold I have, even my 4 cavity brass 250-34-RF isn't this heavy.

[Back_Roads]

 I just checked my 5 cavity out tonight also , same as Waynes, yes quite a bit heavier, I was considering selling my 2 cavity .217 FN BT since this 5 cavity makes 4 FN and one HP in a fill. I will have to test and see how I like the Heavy 5 cavity brass mold first. Although it will require less cycles to make many more bullets per fill.

[K.O.]

I like the Brass molds for the pellet molds(Love my NOE 250-34) with the thin skirts... I think them holding the heat is important for my relaxed casting pace...

Me I prefer the 2 cavity molds just easier to keep mold temp even for each cavity... feel it makes  for best consistency... plus I am just not in a hurry...

I also like the aluminum molds for these rounds they are actually not very hard to cast... but NOE uses high quality aluminum and that matters...

[EdinGa]

Man I wish Money grew on trees... PA sale has the Urban back down at $239 for a day or two...need a couple more..

You're wanting another Urban, and I'm yearning for more power. 😉

My bullets are definitely harder than they were after I cast them. I can't dent them with a thumbnail now. I did manage a small scratch, but that's it.

I shot one through my "ballistic play doh" today. It passed all they way through and bounced off the water bottle backstop. I'm attaching a picture of the setup and the recovered round.