⫐ Altaros ATP Smooth .25cal ⫐ Some advice, please ⫐

[JungleShooter]

⫐ Altaros ATP Smooth .25cal (49.5gr)
⫐ Some advice, please.


Can it be done on the platform I have available?
▪ RTI Prophet 2 Compact Performance
▪ .25cal
▪ 70FPE = 800fps MV at the most, more realistic is 750fps MV
▪ 1:20" twist rate
▪ 510mm short bbl, only lightly choked, as it is the RPB barrel supposedly made for slugs and pellets alike


Thanks,
Matthias

 

[Centercut]

It doesn’t seem so, but the only way to know is to try.

 

[Vetmx]

That’s a whole lotta slug for a 400mm barrel. I think you should keep your testing at 33gr and lighter. Even with a 33gr, you’re going to be operating at some unfriendly reg pressures for that little bugger. It will do it though. It’s up to you to decide if the gun is too harsh to be accurate with.

 

[JungleShooter]

That’s a whole lotta slug for a 400mm barrel. I think you should keep your testing at 33gr and lighter. Even with a 33gr, you’re going to be operating at some unfriendly reg pressures for that little bugger. It will do it though. It’s up to you to decide if the gun is too harsh to be accurate with.

Thanks, Mike and Frank.

The gun is the MKII of the Prophet — and that means it gained over the MKI 100mm more barrel in the compact version (510mm).
And it gained the balanced valve and much larger transfer ports — which allows higher powers at lower reg settings.

RTI published the graph below on the HardAir website. It shows which caliber can achieve what power at which regulator setting.
For 70FPE it shows it would need a reg setting of 163bar.

Matthias

 

[Vetmx]

The 510 is the perfect length hunting barrel for the RTI’s. My P2 came with a 600mm RPB and it shoots fantastic. But it didn’t take long for me to order a 510. The 510 was what my Priest 2 had and it opened other doors for keeping the gun compact and quiet. I really wish they made a .30 in 510 instead of 400mm. My .30 is a 600mm and I’m only at 108b to achieve proper pellet speeds. I have a feeling this winter I’m going to make it a 510mm and just bump the reg up. 163b doesn’t sound like much fun but I never went that high with a balance valve RTI. The non balance valve RTI’s would get quite active when you eclipse 140b on the reg.

 

[JungleShooter]

The 510 is the perfect length hunting barrel for the RTI’s.

Well, thank you, that makes me feel good for getting the compact, not the regular OAL. I struggled with this decision for months before committing.

I really wish they made a .30 in 510 instead of 400mm.

They do, the P2 Compact .30 comes with it (chart below). But I can't find it being sold as part....

Matthias

 

[Vetmx]

If it was for sale I would have bought one. All I see is 600mm .30 so that’s what I have.