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Posted: 6/25/2005 11:11:27 AM EDT
| I am assuming as long as you have a forged lower made by a major manifacture it should make a weapon you can depend on. I am assuming as long as you have a top notch upper and it mates with the lower in a tight fit you should be good to go? I know all of the lower parts internals should be by the same manifacture, of high quality of course... Bottom line do I need a lower by RRA or will a Olympic do. If maybe... what do I need to check for? I was under he assumption the upper is the key to good function as long as you had a decent fitting lower? You help would be great. Thanks |
You're right. Most all forged lower receivers will do the job. Just make sure you have a quality LPK installed. The price differences have to do with name brand as well as finish IMO. Most lowers are made by just a couple foundries. |
| Yep you can skimp on the lower. All it does is hold the LPK. You can get high quality lowers cheaper than Oly though. Look at Stag and Mega. Both will be in the $85-100 range and are top notch in quality despite the low price. CMT/Stag also makes a high quality LPK at a good price. |
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Thanks All Just one quick question whats a LPK? (lower parts kit?) I have an olympic preban and someone stated that it would not make a life dependable rifle. I thought it was nonsence however he had some reputation behind him, so it made me think. I plan to use the rifle in a few courses such as Blackwater and possibley bail enforcement if, I take to it like another arm. I knew all lowers were forged by two companies, just who machined them out made the trade name. I didnt think various companies were that off spec. Also it did not seem the lower was just as critical as the upper. Thanks All for the reassurance. Mike K |
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IMO = In My Opinion A preban Oly very well may be a cast receiver. This is probably what your friend was refering too. I just bought and assembled a Stag and a Superior Arms lower. Price was about the same. The Superior went together in a snap. I love it. It was my first build. The Stag I had to work at it a little. It's a bit tighter in places. But I think they have a reputation for this. It will loosen up with time and use. And being tighter to begin with it should stay snug for a very long time. I do have to use a tool of some sort to push out the take down pins, for example. I used Stag/CMT LPK's (lower parts kits). They are great! You can find cheaper kits, but I doubt they'll be better. I'm sure I'll build more AR's but I really don't think I'll use anything but a CMT lpk. I'm sold. |
| Like Bob said your preban Oly could be cast. Call Oly and give them the SN and they will tell you. If it is forged you are fine. If not for I believe $100 you can send it back to Oly and they will manufacture a new forged receiver for you and stamp it with the same pre ban SN. They then destroy the old lower. Also Oly is the only company that actually manufactures it's own receivers. They manufacture all of their parts for that matter. Making them the only true AR15 manufacturer. |
Nah, sell the Oly to a guy in a state with an AWB, then use the procedes to buy a new lower. You are correct with the assumption that the lower isn't the most critical component on the rifle. As long as you get a good forged one, you won't have a problem. Just stay away from Vulcan/Hesse. The list of good lowers is extensive. Keep an eye on these boards, and you will realize that most people have good luck with Mega, Stag, RRA, newer Oly forged, Bushmaster, Superior Arms, Ameetec, etc., etc. There are more good ones, but it's late, and I'm tired, and my brain just ain't working well after being out all day in 95 degree weather with high humidity. WIZZO |
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make sure it is actually a preban and legal for you to own through olympic first. if its forged i dont see any problem with it. i have used various lowers and it's mostly buying a name since there is only slight variation between them. but do go with quality parts! |
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The critical tolerances in a lower where things can go wrong (but seldom do) are mag well dimensions, hammer & trigger pin holes and the receiver extension hole. 1. Mag Well. Some manufacturers can be a bit tight on the mag well dimensions. If the magazine is on the large side of spec, it can have problems. 2. The relationship between the trigger and hammer pin holes have to be exactly right and they have to be drilled at precisely 90 degrees through the receiver. If they are off even a little, the hammer won't properly engage on the sear surface of the trigger. If the holes are angled at all, they surfaces may engage, but not along the entire width and you'll get uneven wear and it will eventually start doubling on you. 3. If the receiver extension hole is not exactly concentric with the bore, it is possible to get some binding when when the bolt carrier recoils during the firing sequence. Now, how likely is this? Not very (staying away from Hesse/Vulcan improves your odds!) With the exception of Oly, the forgings come from a couple of sources who make them for everyone. The final machining can be screwed up, but it isn't likely. Templates for the hole positions make it almost impossible to screw up. While it is possible to have out of spec/tolerance lowers that will cause you problems, the odds are so low its like winning the lottery. |
| Out of spec lowers are not that uncommon even from old AR companies. I recently had a new lower replaced that had the trigger pin hole placed incorrectly on the lower. It was so low the carrier would not push the hammer down far enough to catch the disconnector because of the low placement of the trigger holes. |
This is not necessarily true. I have a cast lower that does not have any raised letters. |
+1 for STAG/CMT |
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