I have recently acquired a like new ACH and have a few questions for experienced users. The helmet came with two sets of green pads sized ‘6’ and ‘3/4’. As it is the helmet is a tight fit with the ‘6’ pads installed (medium helmet; my hat size is 7 1/4) so I am wondering if I can get a set of smaller pads to allow a better fit. Or, should I just reconfigure the pads to adjust the fit. What size pads would be smaller (I assume ‘5’ would be smaller than ‘6’, and ‘1/2’ would be smaller than ‘3/4’) and do users have recommendations on which brand / type of pads to get. I see the pad sets on eBay all the time so finding a suitable set should be easy. Any information is appreciated! 
PRtrooper (paratrooper?)
Are you going to jump it or wear it to board meetings? 
Did it come with the little instruction manual that talks about pad placement, etc? I generally follow what the book says.
I too have problems in the past with pads, but no time to order them from the States, so I ended up cutting mine down by hand. I slit the cloth and pulled out the foam, cut it, and put it back in. Not the best option, but it got a helmet on my head.
BTW, check to make sure it was not made by Armorsource/Unicor due to the recall.
In response to our query on the reasoning behind the recall of 44,239 Advanced Combat Helmets produced by ArmorSource LLC (formerly Rabintex USA LLC), PEO-Soldier informed us that after testing a statistical sample of ArmorSource helmets, results showed that they did not meet Army standards for ballistic protection. We found it unusual for a product to be recalled by manufacturer rather than lot number, and PEO-Soldier went on to explain that the testing was specific to ArmorSource. It was conducted in conjunction with an ongoing investigation by the U.S. Department of Justice, Office of the Inspector General, and the Army concluded that it was in Soldiers’ best interests to recall all ACHs made by ArmorSource.
I saw the soldiers on our FOB standing in formation doing helmet checks this week.
Personally, I would say ditch the pads and go with the Opscore liner kit. Much more comfortable than those pads, and you can dial it in to fit your head.
http://www.ops-core.com/ACH_Occ-Dial_Liner_Kit_P9C5.cfm
Size 4 are 1/2", Size 6 are 3/4", and Size 8 pads are the 1". I have the same hat size, and use a combo of 4 and 6 sizes in my helmet.
http://stores.greygrouptraining.com/-strse-2334/MSA-Ballistic-Helmet-Pad/Detail.bok
EDIT: top add the TM
http://media.msanet.com/NA/USA/BallisticProtection/MilitaryHelmets/AdvancedCombatHelmet/10063328.pdf
Use the pads from a Protec helmet.
Well, the helmet I have was made by Rabintex, so I guess it is one of the recalled ones. It is like new and I intend it to be a SHTF unit to carry in the trunk of my cruiser with a bail-out bag and vest. I’m not really worried about the recall since the thing is quite rugged, and it is a hell of a lot better than not wearing one. For the ultra-low price I paid it’ll work fine. JSantoro, thanks a bunch for the links, I will try to acquire a set of size 4 pads and fit this thing to my squash. 
you’re a better man than me to trust your head with that thing. seeing as the criminal charges they’re bringing against the company and some employees.
Glad I searched “helmet” here. I almost picked up a Rabintex for $200 to replace the Second Chance helmet Iraqgunz stole from me.
All things being equal… Ditch the Rabintex and go to the EE forums and get a replacement!.. you’re only issued one head and finding a replacement ACH is cheap insurance. As pad sets go, I found the Team Wendy’s EPIC pad set a boon to fitting an otherwise too small helmet to my enormous grape. Got a med. SDS Warrior from Iraqgunz and couldn’t get any arrangement of pads to work, then I looked up a thread on LF. com and found a thread about the EPIC… It worked out great and I now have a helmet that fits, is stable and is close fitting for less interference with other gear and will still absorb impact to specification. But don’t keep a substandard piece of PPE and expect it to do it’s job adequately… Just sayin’
Ha! So you bought Gunz’ helmet. He sold it and then got a line on a gig where he’d need one. I gave him mine.
That helmet liner looks like the way I’d go…
Yep… I guess he just had to have the Colt 16" take off barrel I had… Funny how, just when you think you don’t need a piece of equipment and sell or trade it off…
Gunz is GTG then eh? He probably wouldn’t recognize the helmet after I refit it…
Yeah… if you can get him to show up on time.
I had a teammate like that once… Now listed as “ex-wife”… Gunz is a good sort though.
The only thing gunz does quick is lock idiot threads before I can take a pot shot at the dunce who started it!!
be wary of installing pads that are too thin (less than 1/2" or 3/4") between your noggin and the inside of the shell due to back face deformation of the shell. the shell might stop the bullet but you don’t want the inside of the shell contacting your skull from BFD. i’m just passing along this warning from conversations i’ve had with helmet manufacturers.
Is 3/4" a reqirement to mitigate the effects of backface defomation? If so I might wind up with a helmet that looks like one of those old GSG 9 atom ant helmets. And how will soft foam pads keep the helmet from shifting towards your head at the moment of impact and exacerbating the effects of BFD.
as i understand it, the max backface deformation allowed is a little over 1/2" (16mm actually). the 3/4" minimum pad thickness is to have some space between the deformed part of the shell and your head, to reduce the amount of injury due to BFD. i’m not sure i understand the 2nd part of your question. how will they exacerbate BFD vs. what? no foam pads?
the helmet will move. how much it moves towards your head depends on the composition of the pads. most are dual-density - the soft part for comfort and the firmer part to absorb impact/shock and prevent the foam from compressing completely on impact.
I understand there is a denser layer under the soft foam of the pads. my question is, just how thick is this denser layer and does it compress under impact to lessen the stand-off space to prevent impact trauma from backface deformation? I have a good understanding of blunt force trauma in the case of motorcycle helmets but, they use a 1/2" layer of EPS foam to absorb and distribute impact over a larger surface. Most of the combat helmets use a combination of open and closed cell foam to attenuate trauma to the head and even closed cell foam collapses faster than EPS. So… my question is, can the pads compress enough to render the 1/2" standoff negated by the impact of a standard military round?
on the 3/4" pad, the denser layer is 1/2" thick (on the approved team wendy pads and equivalent).
in addition to blunt impact, the helmet pads have to deal with impacts that the motorcycle helmet doesn’t - impact from shock waves and projectiles. the pads also have to return to shape - EPS doesn’t, which is why you’re supposed to replace a motorcycle helmet after you’ve had an impact with it.
when a helmet is struck by a projectile, the impulse is much quicker than blunt trauma impacts, so the pad does not have time to compress fully. if you take a team wendy pad and squeeze it between your index finger and thumb, you can compress it almost all the way until they almost touch. if you jab the pad quickly with your finger, you get almost no penetration. the quicker the impulse, the less compression you get.
will the pad compress enough to negate the 1/2" standoff? not according to the research/testing. there are circumstances under which it may reduce it, but not negate it.
now, note that the ‘standard military round’ you’re referring to are handgun bullets and frag; not rifle rounds.
Well that resolves a question I had about the composition of the average ACH pad… Now about the Team Wendy EPIC liner… According to the site the liner is sufficent to protect the head and the comfort pads are for stabilization of the helmet and not intended as stand-off devices, the question is… is this proven?