Gonna build my first AR 9mm lower (this is the lower I have in route)

https://www.aimsurplus.com/pro...e+mags&groupid=11110

and wanted to ask if I need to or should purchase only a Spikes LPK to go with this Spikes AR 9mm lower or will most reputable brand name LPK work? Being my first build I prefer not to have to modify any parts to fit if possible...Thanks for your help...Mark

Are most LPKs the same? Short answer: Yes

I have never had to modify any LPK kits, I have had to buy new parts when springs went flying

Only part I can think of that will be different for the 9mm AR is the BCG.

I've noticed small differences in individual components in LPKs from various vendors, especially the magazine catch, trigger group, selector and bolt catch. Different finishes, mold marks, etc. I've only ever had one part that was out of spec enough to need replacing (a selector that had bad detent stops).

Different vendors can cut corners to save a small amount of bucks to sell you their stuff. I've seen selector detents that were not properly hardened/coated to save a couple of cents per, that wore out after about 20 applications.The same applies to bolt catches which turn out "beaver chewed" after the same 20 tries. Do your due dilligence on whatever you buy. Cheaper is not always better IMHO.Buy once cry once, rather than save 15-20bucks and regret it later.

I used to get Rock River LPKs they are top notch.

I have switched to these as they are much more customizable so I don't have to buy duplicate parts if I want to tweek the kit
https://www.redbarnarmory.com/...rbacustomar15lpk.htm

Though last build I stumbled upon a full Colt Target Match LPK so I had to snag it.

I've found the CMMG LPK's to be my choice, after trying a lot of different brands. They've got a slick, shiny finish vs. the rough phosphated finish from PSA and others. Makes for a nice feel set of controls, especially the takedown pins which have a lot less stiction in comparison

Most QUALITY AR LPK are the same, however, you do get what you pay for.

Definite difference in quality between US made and foreign (Taiwan) made LPK.

Some use cheaper roll pins, and some use coil pins.

They are all the same but I only use them sans the grip and trigger.
All my builds are upgrades in those areas.
YMMV

For a 9mm build, I'd recommend a 9mm Specific parts kit. IIRC the Hammers are different because there are differences between a 9MM BCG and 5.56mm BCG. Between5.56mm LPKs you can spot small differences (casting seams, different grip screws and springs, plastic vs cast magazine release, etc.), if you do a side by side comparison. Price doesn't always directly relate to quality. I actually liked the Stock trigger on the older Stag LPKs($69) over the DD LPKs($99), but your mileage may vary. I found a couple manufacturers I trusted and stuck with them.

quote:

Originally posted by CD228:
For a 9mm build, I'd recommend a 9mm Specific parts kit. IIRC the Hammers are different because there are differences between a 9MM BCG and 5.56mm BCG. Between5.56mm LPKs you can spot small differences (casting seams, different grip screws and springs, plastic vs cast magazine release, etc.), if you do a side by side comparison. Price doesn't always directly relate to quality. I actually liked the Stock trigger on the older Stag LPKs($69) over the DD LPKs($99), but your mileage may vary. I found a couple manufacturers I trusted and stuck with them.

Pretty much everyone is cutting the 9mm BCGs for standard AR hammers anymore. So that is not an issue. If by chance one happens to get one that does it is a very simple fix with quick trip to Adco.

I have put together a few different lowers for myself and friends and parts seem to vary,especially the springs. The cheaper kits usually come with cheaper/thinner springs that will not hold up well for the long haul. I have had a few break after only a few hundred rounds through them. I use CMMG parts kits and they are not much more than the cheaper ones and have never had a bad part or spring. I can't remember what parts kit I bought from PSA during the 10 year ban we had but I bought the cheaper kit, as it was still expensive at the time and about all I could find. I think it was Black Hawk,their lower end brand, but I could be wrong. It was the worst kit I have ever used. A few parts were out of spec and you could easily see it and again the springs were garbage.

CMMG is where I will start....Thanks guys for the direction and feedback...Mark

quote:

Originally posted by Black92LX:
I have switched to these as they are much more customizable so I don't have to buy duplicate parts if I want to tweek the kit
https://www.redbarnarmory.com/...rbacustomar15lpk.htm

Oooo, that's a nice find there.

I'll be using them.

It's exactly what I was looking for. I wanted a LPK but to drop in a CMC trigger with Magpul grip and Magpul trigger guard.

Last 2 builds used ALG Kits.

I'd have no problems using theirs again, or BCM.

I will pay a bit extra to make sure that kits are complete (and in my perception, likely of higher quality/choice small bits)

In my experience there are some significant differences in quality.

A buddy of mine bought some cheap no-name stuff on ebay or somewhere.....

Had all kinds of function issues. We traced most of them to junk springs. One to a junk fire control group.

I saw a guy with either a dpms or Olympic arms kit go full auto in a class. Hammer pin broke. Poor heat treating I assume.

Can't go wrong with either CMMG or BCM. They make nice LPK's as does Spikes Tactical from my personal experiences.

I would be wary of no name kits. However, I wonder how many parts are all coming from the same source?
Just because it has a big name label doesn't mean it is manufactured by them.

I really like the Spike’s enhanced LPK. To me it feels very solid/crisp when firing, virtually zero slop. May not be the lightest trigger pull out there, but I like it. I’ve used CMMG and a few others for what’s its worth as well, but strictly Spike’s on the last few.