Current Sionics Gas Ports

AR/M4 AR General Discussion
1

Does anyone happen to have measurements on the current production Sionics barrels? I’m looking at the 12.5 and 11.5 lengths.

I did email them a few months ago asking this question, but they said to call them. I called and spoke to one of the guys, but he wouldn’t give a size. While I’ve bought from them in the past, and I’m sure they know what they’re doing, I’d like to have an actual size rather than “trust us, we don’t over gas our barrels like the other guys”.

I looked at older threads with posted GP sizes, but it looks like they’ve been changing throughout the years. I also see that under complete uppers they have options for “ERGP” and “Dedicated Suppressed Use” on top of whatever their standard GP size is.

Thanks

2

Haven’t seen current Sionics stuff at all. Do they still offer the “RGP”? That is the perfect unsuppressed port size.

3

I don’t see an RGP on their website. Just standard, ERGP, and Dedicated Suppressed Use which is something I haven’t seen from them before.

It makes me wonder if “Dedicated suppressed” is just what the old ERGP was, and then maybe ERGP just took the place of RGP.

But it’s hard to know without any published sizes.

4

Sucks that they had to complicate things like that. RGP and ERGP was fine.

5

If they don’t want to disclose size I’d just move on to someone else.

It’s some huge secret. It’s easy to measure if you have a set of drill bits, and pin gauges are cheap enough.

So why bother not telling someone something they can easily figure out?

I guess last option is order a barrel or two measure the gas ports when you get them and return what you don’t want.

6

I found them easy to work with. I called them, told them what I wanted, they told me what to buy, and they FSB’d it by my request. This was a few years ago, but it mirrors every experience I’ve had with them.

7

I’ve read that they stopped with the FSB reaming/pinning. Things may have changed… I too haven’t bought from them in years.

8

I don’t see the need to obsess about gas port size anymore with Clint’s gas tubes available. If you’re buying duty grade equipment form solid companies, you’re probably going to be fine. If it turns out it’s not exactly what you want, just put in a BRT gas tube. I think he even offers them in custom port sizes.

9

I agree with all your points. It’s just that their 12.5” barrels check all the right boxes for me, minus the unknown of the GP. There just aren’t that many options with 12.5” barrels out there, or I’m not looking in the right places.

And the thing is I’m pretty sure one of the 3 options of GP size they have would be just what im looking for, but it’s a guessing game as to which one it is. And while doable, it’s a hassle to buy all 3 and measure the port sizes and then return the other two.

For what it’s worth, I did buy the 12.5” standard GP sized barrel a few weeks ago. At the time the ERGP and Dedicated Suppressed weren’t listed on their site. It wasn’t until the other day I saw them pop up on their website. Which prompted the question.

I’m overseas for the moment, so there isn’t really anyway for me to measure the gas ports until I return anyway.

I’m sure the BRT gas tubes are good quality kit, and I probably wouldn’t hesitate to try one out if needed. But if I’m buying a barrel I’d rather just have the GP right from the start.

10

I have a pair of 11.5" that are less than 2 years old. As I recall, they are 0.0625" ports.

11

Agreed! Plus those tubes aren’t cheap!

12

I’ve seen Sionics 12.5” barrels mentioned a few times, but don’t recall ever seeing one on their website.

13

Are yours the RGP or ERGP barrels?

Yeah they’re not cheap, but still a good fix if you happen to already have an over gassed barrel vs tossing the barrel and finding a new one. But like I said earlier, if I’m starting with a stripped barrel I just rather have it right from the start.

They are up on their site now. Im not sure how long they’ve been there, but I also see a 14.8” length as well.

14

Mine are considered the standard barrel. At the time the barrels were purchased, you only had the choice between standard and ERGP. From what I’ve read, the RGP became the standard barrel at some point prior.

15

Agree on both points.

16

I can’t find my notes with the gas port size on my Sionics 12.5 mid-length barrel. I’ve only shot it with AE 75grain TMJ and Speer 75grain Gold Dot, but it’s perfectly gassed with an A5H2. Ejection is at 3:30 and it’s VERY soft shooting. With a Surefire Mini it ejects at 2:00.

I’ve been very happy with this barrel. I’ve shot four of them and they’ve all been 1.75" or less for 10 shot groups. Mine is consistently under 1.5", often at 1.25" for 10 shots.

17

I hope that’s still the case today. Regardless, I ended up ordering another one but in ERGP. When i get home before the New Year I’ll take measurements of the two and post what i find here.

Interesting, i had no idea they ever offered a 12.5 midlength.

18

I wanted to give an update. I have a Sionics ERGP 12.5" midlength barrel that just came in and I was able to get a look at the gas port.

Unfortunately, I couldn’t get an exact measurement because I don’t have the right pin gauges.

However, I was able to confirm that it is smaller than 0.073.

0.073 was the smallest pin gauge I had on hand, and it didn’t fit. This is the Extreme Reduced Gas Port barrel, and it is a midlength. Hopefully I can have this built into an upper soon.

19

I don’t think they’d spec that as the standard gas port; .0625 would get reliability complaints in a 11.5” unsuppressed. I think the RGP used to be .070”, which never made sense to call “reduced” or full-time suppressed….its a normal gas port size thats been used by Colt and BA for unsuppressed guns successfully. “Standard” is the right name for it.

20

When I bought mine a few years ago, they offered standard, RGP, and ERGP. I think the reduced was .0625”, and mine has been completely reliable unsuppressed. I’ve been running random hand loads nowhere near full 5.56 pressure…unsuppressed.