Top to bottom) 23mm NR/NS-23, 30mm ADEN, 20mm Oerlikon, 50cal M2/M3, 7.62mm Browning. Just thought I'd share a bit of my collection to give food for thought on actual sizings of rounds,
Aimpoint Base and Top Ring 30 mm - Optics-trade
File:Protiletalski top 20 mm Flak 30.JPG - Wikimedia Commons
BIMINI TOP SLIDE 2 PART A4 FOR TUBE 30 MM PART NO 8478430 – Gib Yachts Chandlery
Yusuf Akbaba di Twitter: "IDEX2019'da sergilenen Cockerill yeni nesil taret. 25 - 30 mm top ve 2'li atgm atıcısına sahip. Hafif, orta ve ağır sınıf bir çok araca entegre edilebilir.… https://t.co/mE7WxWQUsc"
BINDER Top Access Port (30 mm) Diameter: 30 mm; For Use With: KMF 720, | Fisher Scientific
Circular sawblade GoldLine 190 x 2,8 x 30 mm. T=24 ATB - BS tools
A-10'un ölümcül silahı: GAU-8 30 mm top | Tolga Özbek
BRAND® stopper red rubber, H 30 mm, top diam. 32 mm | Sigma-Aldrich
11.4018.012.005 RockShox Top Cap Assembly Air 30 mm 30 Gold A1
MK 46 30MM TOP ATEŞİ TESTİ( MK 46 30MM TOP FIRE TEST) - YouTube
Ride 603 Cigar Storage Tube (30 mm Shell casing) Gold or Silver Top Ch
Aselsan Muhafız (Smash 30mm) – Millisavunma.com
BRAND® stopper red rubber, H 30 mm, top diam. 32 mm | Sigma-Aldrich
Soldering nozzle for TOP, 13 x 30 mm - Weidinger.eu
File:Lazar 3 top 30 mm Žandarmerija MUPa Srbije - Odbrana slobode 2019 Niš 1.jpg - Wikimedia Commons
TFMT Style RTA Silver 4mL 30mm Rebuildable Tank Atomizer
SherryBerg 30mm throttle body for yamaha aerox 155 150 top quality replace carburetor carb 155cc 30 mm|Throttle Body| - AliExpress
One pair of Top Hat Reducers - 31.75mm External to 30mm Bore
Top triple clamps Kitaco 30mm tube - MOTORKIT
5mt Top Quality 1.25" (30 mm) White Flat Elastic: Amazon.co.uk: DIY & Tools
Top Zastava 30mm za oklepnik LAZAR II 8×8 | Spletni portal obramba.com