Musste div. Sachen googeln, dieser Post von JackBauer in einem anderen Forum hat alle meine Fragen beantwortet:

CYLINDER: (cylinderVolume-to-barrel-ratio) 2 is to 1 (standard)
Marui Stock Cylinders:
1. Closed Cylinder = 27.1cc 450mm(min) 580mm(max) barrel length
2. XM Cylinder = "4/5 hole" = 364mm(min) 460mm(max) barrel length
3. M4 Cylinder = "3/4 hole" aka Type-2 17cc - 229mm(min) 430mm(max) barrel length
4. MP5K Cylinder = "mid hole" 9cc 110mm(min) 170mm(max) barrel length

Systema NB Standard and BoreUp Parts:
1. Type-0 Cylinder (closed) fits M16-A1,VN,A2,G3-A4,SG1,SIG550,AUG
2. Type-1 Cylinder (tip hole) for XM177, M4, AK47, AK47S, SIG551
3. Type-2 Cylinder (XM hole) for MP5-A4,A5,SD5,SD6, MC51,SIG552
4. Type-3 Cylinder (M4 "3/4" hole) for MP5 PDW
5. Type-4 Cylinder (MP5K mid hole) for MP5K
*BoreUp Closed 29.4cc = 500mm(min) 600mm(max) barrel length

KM Cylinder Parts:
*Intercept Cylinder 59 barrel length from 450mm to 590mm (Type 0)
*Intercept Cylinder 45 barrel length from 250mm to 450mm (Type 2)
*Intercept Cylinder 25 barrel length from 100mm to 250mm (Mid-hole)

*To avoid confusion, don't mix brand model names, just model equivalence
*TM M733 by stock is closed cylinder (Type 0) -over ratio

BARREL: (inner barrel length)
650mm/25.59in PSG-1 (extended)
595mm/23.42in APS2 OR
589mm/23.18in PSG-1
550mm/21.65in M16A1/VN/A2,AUG (extended)
534mm/21.02in Sig550
509mm/20.03in M16A1/VN/A2,AUG
472mm/18.58in Famas SV/F1
469mm/18.46in G3-A3/A4,SG1
455mm/17.91in AK47,AK47s
444mm/17.48in M60
407mm/16.02in M4A1 M653E2 (extended)
395mm/15.55in APS2 SV
369mm/14.52in HK51
363mm/14.29in M4A1,RIS,SR-16,XM177ED,Sig551
300mm/11.81in M1A1,AKBetaSpetz, M733
285mm/11.22in MC51
247mm/9.72in Car15,P90,G36C, SIG552
245mm/9.64in UZI - 400mm/15.74in (extended)
229mm/9.01in MP5A5/A4/SD5/SD6
170mm/6.69in MP5K-PDW (extended)
141mm/5.55in MP5K-PDW
110mm/4.33in MP5K

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