Well I didn't expect this, but I'll live with it

[Mod90]

Just got a new gun yesterday, .177 BT65SB

So I decided to get out & zero at 15 yards before going to the range this weekend to sight in for hunting distances. Pellets were JSB Monster 13.43 grains

But after initial sight in, decided to shoot some groups for grins & giggles, & this is where I received a surprise. This gun consistently prints a ctc 5/16" group on a target at 15 yards. I can't wait to get to the range & have her stretch her legs & see what she'll do at 30->50->75 yards

And this gun is a smooth-bore, that's right, completely smooth, not even a scratch in the barrel.

Pic of the evidence below

[Bwalton]

sounds good.......I would zero @35 and do some 50, 75, 100, and 120 groups.

[Mod90]

That's the plan.
But sadly, that'll have to wait for Saturday afternoon or Sunday.

[BenjiHunter]

Sweet shooting!
I think you mean smooth twist barrel (polygonal barrel).

[Mod90]

No Stefan. I mean smooth bore. not 1 scratch of rifling in the barrel along it's entire length. Here in T&T, legally we can only have .177 smooth bore airguns w/o a firearms permit.

[StevenG]

Pellets are primarily drag stabilized, so that helps. Still awesome groups. Keep us updated.

[BenjiHunter]

No Stefan. I mean smooth bore. not 1 scratch of rifling in the barrel along it's entire length. Here in T&T, legally we can only have .177 smooth bore airguns w/o a firearms permit.

In that case, those groups are incredible!!!
Congrats to an awesome rifle!

[MicErs]

Pellets are primarily drag stabilized, so that helps. Still awesome groups. Keep us updated.

This is true only at short ranges.  As the range increases rifling becomes more and more important.  A smooth bore that shoots .375 CtC at 15 yards will likely shoot about six inches at 50 yards.  A rifled gun that shoots .375 CtC at 15 yards will likely shoot under two inches at 50 yards.

Just an observation, not a criticism.

[StevenG]

You are totally right. Quite likely the high drag on an imperfect projectile magnifies that problem as distance increases and spin is the only tool we have to counter that.

[Mod90]

This is true only at short ranges.  As the range increases rifling becomes more and more important.  A smooth bore that shoots .375 CtC at 15 yards will likely shoot about six inches at 50 yards.  A rifled gun that shoots .375 CtC at 15 yards will likely shoot under two inches at 50 yards.

Just an observation, not a criticism.

Not taken as a criticism, no worries there.

Thats the general principle, but for years now I've been thinking that something doesn't add up. For years I've pondered if rifling is absolutely definitely needed to stabilize diabolo pellets for them to maintain accuracy during a pellets flight path along its given trajectory.

With my other gun,which is also a smooth bore, I can shoot & hit my mark consistently past well past 50 yards, the longest shot I'd try would be 75 yards, and so far I can easily hit a 1" target at that range with no problems. Now I'm not sure if they're tumbling in flight, I don't shoot paper targets so there's no way for me to tell if they're tumbling until I can see how they impact on paper. If they are tumbling I wouldn't be surprised. But the idea about smoothbores being inherently inaccurate at longer ranges & only capable of producing scatter gun groups, for me & going by my experience, doesn't seem to be entirely accurate or  be the have all be all & end all that some may consider it to be.
Or maybe everyone here is really lucky to get guns with invisible rifling 

Check out this video of another local airgunner with a SB M-rod at 33 yards, video quality is kinda poor but it is clear he consistently hits his mark



Then there are the FX Smooth Twist barrels. Those are also SB with, only a few inches of rifling for about 2-3 inches from the muzzle iirc, at an extremely slow twist rate.

I'll try to print some shots at 20 30 40 an 50 to see what the pellets are doing in flight & report my findings.

[pyroboy33]

This is true only at short ranges.  As the range increases rifling becomes more and more important.  A smooth bore that shoots .375 CtC at 15 yards will likely shoot about six inches at 50 yards.  A rifled gun that shoots .375 CtC at 15 yards will likely shoot under two inches at 50 yards.

Just an observation, not a criticism.

Not taken as a criticism, no worries there.

Thats the general principle, but for years now I've been thinking that something doesn't add up. For years I've pondered if rifling is absolutely definitely needed to stabilize diabolo pellets for them to maintain accuracy during a pellets flight path along its given trajectory.

With my other gun,which is also a smooth bore, I can shoot & hit my mark consistently past well past 50 yards, the longest shot I'd try would be 75 yards, and so far I can easily hit a 1" target at that range with no problems. Now I'm not sure if they're tumbling in flight, I don't shoot paper targets so there's no way for me to tell if they're tumbling until I can see how they impact on paper. If they are tumbling I wouldn't be surprised. But the idea about smoothbores being inherently inaccurate at longer ranges & only capable of producing scatter gun groups, for me & going by my experience, doesn't seem to be entirely accurate or  be the have all be all & end all that some may consider it to be.
Or maybe everyone here is really lucky to get guns with invisible rifling 

Check out this video of another local airgunner with a SB M-rod at 33 yards, video quality is kinda poor but it is clear he consistently hits his mark



Then there are the FX Smooth Twist barrels. Those are also SB with, only a few inches of rifling for about 2-3 inches from the muzzle iirc, at an extremely slow twist rate.

I'll try to print some shots at 20 30 40 an 50 to see what the pellets are doing in flight & report my findings.

Man I'm super curious to see groups out of that smooth-bore at 50+ yards, it should be real interesting. I've never really heard of smoothbores being super accurate but it may be different with pellets, who knows...

Also, just curious but what are the firearm laws like in T&T? Seems like all the stupid restrictions on AG's  that you have to deal with make it almost not even worth it...

[Mod90]

Getting a firearm permit here kinda goes like this

1-Get a provisional license, this is to be used to learn firearms safety at an approved range
2-Fill it out & drop it off at the police hq, along with a police cert. of character copy of photo ID, medical showing you're physically capable, & all the prayers you can spare (it'll literally take them a decade or 2 for them to get back to you, unless you're either well connected or extremely lucky)
3-After you're done learning at the range & deliver your proof of this to them, you get your permit to keep & carry within a year or two

Then you have to deal with the local gunsmiths. Honestly, imho they're a bunch of land pirates. You fellas wouldn't believe what we are forced to pay for our guns ammo & accessories here. But I'll give you an example.

The Sumatra 2500 Carbine pcp retails for USD 649.99 The TTD:USD exchange rate is currently about TT$6.499 to USD$1.00 What it should cost should be around TT$4225.00
The local dealer for that gun here sells it for roughly TT$25300.00

[Gatorproof]

Getting a firearm permit here kinda goes like this

1-Get a provisional license, this is to be used to learn firearms safety at an approved range
2-Fill it out & drop it off at the police hq, along with a police cert. of character copy of photo ID, medical showing you're physically capable, & all the prayers you can spare (it'll literally take them a decade or 2 for them to get back to you, unless you're either well connected or extremely lucky)
3-After you're done learning at the range & deliver your proof of this to them, you get your permit to keep & carry within a year or two

Then you have to deal with the local gunsmiths. Honestly, imho they're a bunch of land pirates. You fellas wouldn't believe what we are forced to pay for our guns ammo & accessories here. But I'll give you an example.

The Sumatra 2500 Carbine pcp retails for USD 649.99 The TTD:USD exchange rate is currently about TT$6.499 to USD$1.00 What it should cost should be around TT$4225.00
The local dealer for that gun here sells it for roughly TT$25300.00

First buddy let me say,
How many trees are left for target practice? Lol, lol. Sorry, I am in one of those wacky moods again today.

2) do they open or exray incoming parcels¿
3) not that I would suggest anything illegal, but what if someone mailed you a stock barrel for your BT?

You would have the best shooting gun in the country, lol.

If you slip your barrel off , and push a pellet through from the breech end of the barrel, do you feel a chock at the end?

That, I am guessing would help, the chock, I mean.

Be Well,
Gator

[Mod90]

Always goofing around eh Gator 
The barrel is choked, so I guess that is helping a lot with the accuracy. So far as is my experience, accuracy with smooth bores isn't as terrible as some might think, & I'm not too interested in swapping the barrel, at least not yet.