SACair Forum

While i was at the game today, someone suggested that i put a tightbore barrel on my CA M15A4. But i dont know what it is or what it does. So can i get some info? Advise is appreciated.

don't listen to them.

a tightbore has a smaller inner diameter than your "standardbore" barrel. The effects of such is very much debatable by everyone. Most are exaggerated truths and some are only the mere perception of reality.

[quote="freq88"]a tightbore has a smaller inner diameter than your "standardbore" barrel. The effects of such is very much debatable by everyone. Most are exaggerated truths and some are only the mere perception of reality.[/quote]

The slighest wind outweighs the helpfulness of a tightbore.

[quote="MetalMaster"]The slighest wind outweighs the helpfulness of a tightbore.

[quote="JohnnyJihad"][quote="MetalMaster"]The slighest wind outweighs the helpfulness of a tightbore.

LOL you are right...

I was?!?! Awesome, I didn't think I was actually learning anything in math class.

I am a machinist so to me 400ths of an inch is like a mile, in machinist lingo we would say 40 thousandths instead. A couple of the parts that I make at work have a tolerance of +.0002 -.0003 for a proper bearing fit.

I'll buy a used tightbore to increase the selling value of a gun...

[quote="Despise"]I am a machinist so to me 400ths of an inch is like a mile, in machinist lingo we would say 40 thousandths instead. A couple of the parts that I make at work have a tolerance of +.0002 -.0003 for a proper bearing fit.

all the stuff said on here is good advice.

Tightbores are useful for a minor increase in FPS as mentioned many times above.

I put a 6.04 tightbore in my Seal CQB.

I have ran tests on that fps issue, and I can tell you for a FACT we are only talking 5-10 fps. I have tested aks, m4s, pistols and mp5s. I can build a box with compression like you can't imagine. The point is $60 for a 10 fps increase is a waste of money period. You will find out a lot of "upgrades" are NO better than stock parts and provide no real improvement to your gun other than you can say its upgraded.

I have had one good experience with a tightbore before and that was with my TM 5.1 and a PDI 6.01 inner. With upgraded recoil springs and the TB it was shooting 375 fps.

[quote="JohnnyJihad"]I have ran tests on that fps issue, and I can tell you for a FACT we are only talking 5-10 fps. I have tested aks, m4s, pistols and mp5s. I can build a box with compression like you can't imagine. The point is $60 for a 10 fps increase is a waste of money period. You will find out a lot of "upgrades" are NO better than stock parts and provide no real improvement to your gun other than you can say its upgraded.

I have a LRB in my WA p14 45. I run .36s trough it it had insane range. But again it does not need a bucking like most GGB.

Ok Johnny what is the best way to improve the accuracy of a AEG. Say a CA M15 A4 CQB.

[quote="Spooky"]Ok Johnny what is the best wait to improve the accuracy of a AEG. Say a CA M15 A4 CQB.

Thank you, I will stop by the shop later this week.

[quote="MetalMaster"]I have had one good experience with a tightbore before and that was with my TM 5.1 and a PDI 6.01 inner. With upgraded recoil springs and the TB it was shooting 375 fps.

I have a semi-educated guess on the loss of fps with a gbb combined with a tb barrel: the propane released in the firing cycle is sudden and 100% of the propelling pressure. The effective added resistance of a tb causes more of the propane to escape around the breech end of the barrel, rather than propelling the bb down it. With an AEG, the pressure develops as the piston travels down the cylinder. Relatively speaking, it's a gradual pressurizing vs. the gbb "instant" pressure. Like I said, educated guess...

As far as suppressors go you can't go wrong with the G&G ss-100 from AEX. it's about $25. I slapped it on my P90 for kicks and it actually quiets it quite a bit. If I could find my silencer adapter for my MP7, I'd tell you how it sounded...if you're gonna sell you silencer adapter by chance, let me know. I'd buy it. ;)

If you run your mp7a1 in a holster like I do currently, use a g&g ss-100 or ss-80. the both do a great job of keeping the muzzel pop down, especially if you use single shots

I use a Prometheous barrel and do notice enough difference to make it worth the extra $$.

[quote="Editor"]I use a Prometheous barrel and do notice enough difference to make it worth the extra $$.

I currently run a tightbore in my M15A4, very similar to yours, and I have noticed a considerable difference... FPS - from ~374 to ~395, 20 shot grouping @ 30' - ~12" to ~5" (no wind of course), fewer "stray" bb's... If you are a using your gun as a bb hose then not worth it but if you have the $$ and are a single shot guy I'd say it is probably worth it.

An AEG and a gas gun (using expanding gases...not HPA) operate differently. In the former the volume of air expended is fixed, as the piston has completed its compression cycle. In the later the volume~pressure "often" continues to increase due to gas expansion after initial release. Guys who have worked on classics, gas powered snipers or "neo"-classics will testify to the velocity increase of a tight-bore when running Co2 or Propane.