So which are your favorite guns/hosts to shoot?
I'm about ready to get a M16A1 as my first MG... but I'm also considering a HK sear or a M60. I initially budged $25k... then $40k... and now $60k with another year of working overtime and saving money lol.
I really enjoy my MP5K and SD hosts ... but they are the newest additions!
If all things are equal I would just be looking for the best deal and jump into whichever you can afford comes along first; money in hand give you buying power. Machine Guns are a great investment no matter if you buy a safe queen or a shooter, they're all going up exponentially ... personally I look for a well cared for used gun so I can shoot it and it will still be nice enough that it will have re-sale value.
If I were to do it all again:
I'd get the HK sear first as they seem to be going up the quickest and have the smallest number available.
Next the M16 ... there are way more of these around than HK sears because you have not only Colt but other makers as well as conversions and RDIAS's
Last would be the M60 as it doesn't have any caliber conversion, it is what it is ... a pig and only configuration conversions ... and the M60 will also be the most expensive to feed ... don't get me wrong, I'd love to have one but it will have to wait until I win the lottery!
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A couple guns to consider are the MAC10 and M11 ... company called LAGE is making uppers from 380 to 223 for them ... and they are getting great reviews and the platform gaining popularity because you can still get in for 7-10K ... in 2012 the average price on one was about $3500 ... I missed the boat on those! Same goes for an UZI registered receiver or registered bolt ... in 2012 they were around 6K for a bolt and 8 for a registered receiver; now they're 12-15 ... of course there are still Thompson's, Grease-Guns, Sten's and the like ... look on Sturm's and Bowers boards ... don't limit yourself to auction sites as there are 2 big MG dealers that jack the prices way up!
HK hosts are generally more expensive ... even an Omega barreled receiver (which I've had good luck with both of mine) are around $1,400 but you can also roll the dice and look at options like the Century 93, but other than that they aren't cheap.
The M16, furniture and uppers are much less expensive ... mine originally had a 20" barrel and triangle handguards ... but I immediately put a UBR stock and picked up a de-milled 11.5" 5.56 Commando kit for $700
Next I bought a 10.5" 9mm demilled kit that came with a 3-rnd burst trigger and everything else including mag block and 2 mags and correct buffer for $600(BTW you don't "have" to rivet the block into the mag-well, the Colt has tension pins that will hold it along with the mag catch) and I didn't have to dick around with it to get it to run because all the parts were designed to be used together ... again, complete parts kit.
Last year I picked up the Ares Defense Beltfed MCR upper is the most expensive at $4200 ... but what other 223 beltfed can you get into that cheap? NONE!
One of the most fun uppers is my CMMG PDW in 22LR with a 50 round drum ... its the cheapest to shoot and there is no recoil. If you don't run out of ammo you could write your name in full auto with it!
Finding some parts may take time ... I have an AR57 upper that started life with a 16" barrel and I was ready to dump it; then I found a FA bolt and I cut the barrel down to 8" because my suppressor fits inside the aluminum upper but if I don't want to shoot it suppressed I can use a 5.5" flash hider to extend past the handguard.
Really, it really boils down to what you want the most ... if its the M-60 then go for it first, however I think because of desirability prices on the HK sear and M16 are going up much faster than anything else ... I really thought prices had topped out when I bought mine, but just like the UZI and MAC10/M11, they've all more than doubled since then.
Be aware that not all M16's are created equal ... there are M16 conversions that are the least expensive but I've read they can be problematic if the "3rd hole" wasn't drilled exactly correct ... but if the price is right a competent SOT can fill and re-drill and refinish it.
There are also registered drop-in auto sears (RDIS) for AR's ... again, not all are created equal ... try to get one with a steel frame, I've read on-line the aluminum ones can wear and break. but I have no personal experience with them.
Sorry if this doesn't help!