How to identify which pattern bcg - Page 1

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[ARCHIVED THREAD] - How to identify which pattern bcg

Posted: 7/13/2018 9:28:17 PM EDT

I'm buying parts for a Glock style 9mm build and have a question about trying to identify if a bcg will work. Does anyone know if the Spikes bcg is compatible with both Glock and Colt? On the recluse rifle, they have the option for either but when looking up reviews on just the bcg I only see mention of Colt. I've tried looking up how to identify the difference but haven't had much luck.

*Trying to get back to a person quickly on if I'll buy his otherwise I would have gone directly to Spikes with the question. Thanks for any help.

Posted: 7/13/2018 9:59:04 PM EDT

[#1]

Quoted:
I'm buying parts for a Glock style 9mm build and have a question about trying to identify if a bcg will work. Does anyone know if the Spikes bcg is compatible with both Glock and Colt? On the recluse rifle, they have the option for either but when looking up reviews on just the bcg I only see mention of Colt. I've tried looking up how to identify the difference but haven't had much luck.

*Trying to get back to a person quickly on if I'll buy his otherwise I would have gone directly to Spikes with the question. Thanks for any help.

View Quote

Maybe a pic of the bottom and face of the bolt might help to ID what you have.

_

Posted: 7/13/2018 10:06:26 PM EDT

[#2]

if you can't get a direct answer from a reader, and indirect answer... the Glock format bolt must feed from the center of the magazine without striking the sides of the magazine, the Colt format bolt must strip rounds from both sides of the double stack... my PSA bolt works with both formats and measures .290" across the bottom of the bolt, where the bolt strips the cartridges from the magazine

Posted: 7/13/2018 10:35:20 PM EDT

[#3]

Quote History

Quoted:

Maybe a pic of the bottom and face of the bolt might help to ID what you have.

_

View Quote

I’ll try to get a picture of the bolt from the seller.

Posted: 7/13/2018 10:44:25 PM EDT

[#4]

Quote History

Quoted:
if you can't get a direct answer from a reader, and indirect answer... the Glock format bolt must feed from the center of the magazine without striking the sides of the magazine, the Colt format bolt must strip rounds from both sides of the double stack... my PSA bolt works with both formats and measures .290" across the bottom of the bolt, where the bolt strips the cartridges from the magazine

View Quote

I know these are one piece instead of the separate bolt and carrier in a normal AR, but am I only going to look for differences in the “bolt” or would the carrier have differences as well? Don’t have pictures to go off of yet so I’m trying to make sure to ask for everything I need upfront instead of giving him the run around.

Posted: 7/13/2018 11:25:52 PM EDT

[#5]

Actually....there are two types of blowback AR pistol caliber bolts.....Colt (has the ejector in the lower) and Olympic (has ejector in the upper). The Glock bolt is simply a Colt pattern bolt that has a clearance cut to accommodate the single feed Glock magazine.

Posted: 7/14/2018 10:35:32 AM EDT

[#6]

Quote History

Quoted:

I know these are one piece instead of the separate bolt and carrier in a normal AR, but am I only going to look for differences in the “bolt” or would the carrier have differences as well? Don’t have pictures to go off of yet so I’m trying to make sure to ask for everything I need upfront instead of giving him the run around.

View Quote

The bottom where the ramp is.

https://www.wingtactical.com/firearm-parts/ar-15/upper-receiver-parts/bolts-carriers/spikes-tactical-9mm-ar-bolt/

According to advertisements, and assuming this is the same version, it's stated to work with both.

Posted: 7/14/2018 2:00:31 PM EDT

[#7]

Quote History

Quoted:

The bottom where the ramp is.

https://www.wingtactical.com/firearm-parts/ar-15/upper-receiver-parts/bolts-carriers/spikes-tactical-9mm-ar-bolt/

According to advertisements, and assuming this is the same version, it's stated to work with both.

View Quote

Thank you very much. I’ll pass this along and hopefully it is the same one.

Posted: 7/14/2018 3:16:18 PM EDT

[#8]

Worst case scenario and it isn't Glock Cut.....not a big deal to do it.....all it takes is a few minutes with a 1/4 inch ball nose endmill.....I've done hundreds....just give me a shout once you have pics, I can tell you for sure.

EDIT: I just googled and found some pics of the bolt...the one I found pics of is not cut for Glock lowers. This is the one I looked at Spike's bolt

Posted: 7/14/2018 6:43:33 PM EDT

[#9]

Quote History

Quoted:

EDIT: I just googled and found some pics of the bolt...the one I found pics of is not cut for Glock lowers. This is the one I looked at Spike's bolt

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Just for the sake of us that don't get these details...what can you identify in the picture that shows this?

It's seems virtually everyone states compatibility with both these days, and I suspect that is something that's changed over time. My bolt is generic, but I've run with Glock only on a non-LRBHO receiver set. I believe that's a seperate issue from the mag feeding ability, and one I don't currently have to deal with.

Also, if you're willing to share some knowledge, is there a benefit to a Colt-specific, or Glock-specific bolt..or are those marketed as universal just as good?

Thanks for any thoughts you might share.

Posted: 7/14/2018 7:01:31 PM EDT

[#10]

Quote History

Quoted:

Just for the sake of us that don't get these details...what can you identify in the picture that shows this?

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Glad I'm not the only one still having trouble seeing the difference between the two. I guess I'm overlooking it because these 2 look pretty much the same to me.

Attached File

Posted: 7/14/2018 8:11:39 PM EDT

[#11]

Quote History

Quoted:

Just for the sake of us that don't get these details...what can you identify in the picture that shows this?

It's seems virtually everyone states compatibility with both these days, and I suspect that is something that's changed over time. My bolt is generic, but I've run with Glock only on a non-LRBHO receiver set. I believe that's a seperate issue from the mag feeding ability, and one I don't currently have to deal with.

Also, if you're willing to share some knowledge, is there a benefit to a Colt-specific, or Glock-specific bolt..or are those marketed as universal just as good?

Thanks for any thoughts you might share.

View Quote

See the flat on the bottom with the small hole in it (for the pin that holds in the extractor), On a glock cut bolt that will be relieved. I usually do it with a ball nosed endmill.
As far as one being better than the other....the bolt I sell on maconarmory.com will run with both. I have and shoot both Colt mag and Glock mag guns.....I'd post a pic....BUT they are all at the shop....and I ain't goin back till Monday...

Posted: 7/15/2018 6:52:34 AM EDT

[#12]

Posted this before, but still have the image saved.

The left 2 bolts are 'Glock cut' by different manufacturers. See the area on the bottom left of the bolt faces? The bolt faces have been cut so that the bottom of the bolts will slide between the more narrow feed lips on a Glock magazine (more narrow than on a Colt style SMG magazine). The bolt on the right is an unmodified Colt SMG bolt.

There is definitely an angle cut on the bottom of the bolt in the photo you provided. Whether it is enough for clearance I do not know. Rudy (Mad Machinest) might know since he does these cuts.

Posted: 7/15/2018 12:08:41 PM EDT

[#13]

I have a heck of a time telling from just a picture...I practically have to set the bolt on top of a mag, preferably in an assembled receiver set. You can really see then.

Anyway, was thinking the Spike bolt looked just like mine, but that's not the case. Mine is milled just like the middle photo, and I assume a ball mill would produce something like on the left.

A better picture would do it much justice, I think.

Posted: 7/15/2018 1:20:03 PM EDT

[#14]

Dave,

Excellent pic......and the Spikes under discussion I am pretty sure is closest to the bolt on the right in your pic. Won't know for sure till OP can get up a pic.....BTW I'm saving that pic if you have no objection..

Rudy

Posted: 7/15/2018 5:28:02 PM EDT

[#15]

Quote History

Quoted:
Dave,

Excellent pic......and the Spikes under discussion I am pretty sure is closest to the bolt on the right in your pic. Won't know for sure till OP can get up a pic.....BTW I'm saving that pic if you have no objection..

Rudy

View Quote

Hey Rudy,
This question comes up every so often, so feel free to use the picture. I don't remember who made the bolt in the middle, but I believe the one on the left is one of the bolts I purchased from you at Knob Creek.

Dave

Posted: 7/15/2018 7:08:23 PM EDT

[#16]

Quote History

Quoted:
Posted this before, but still have the image saved.

The left 2 bolts are 'Glock cut' by different manufacturers. See the area on the bottom left of the bolt faces? The bolt faces have been cut so that the bottom of the bolts will slide between the more narrow feed lips on a Glock magazine (more narrow than on a Colt style SMG magazine). The bolt on the right is an unmodified Colt SMG bolt.

There is definitely an angle cut on the bottom of the bolt in the photo you provided. Whether it is enough for clearance I do not know. Rudy (Mad Machinest) might know since he does these cuts.

View Quote

Thanks so much for the picture and explanation. I've asked for a photo of the blot face so look for the extra cut and will post it once I get it. I think with what you've provided that I can figure it out, but if you all don't mind double checking me I'd appreciate it.

Posted: 7/15/2018 8:34:57 PM EDT

[#17]

Just an FYI but not all glock bolts are created equal. PSA has at least 1 gen of hybrid bolt that is proprietary and won't work outside of their line of product. Dk about the universality of the spikes, but the spinta I have tends to not care as much about the mag and magwell adapter combo.

Posted: 7/17/2018 9:29:08 PM EDT

[#18]

Looks like it’s not compatible with Glock mags from what ive seen from above but though I’d share the picture. Thanks for the explanation of what to look for so I’ll now know what to look for.

Attached File

Posted: 7/17/2018 9:48:08 PM EDT

[#19]

You are correct......but it can be modded....I've cut hundreds of them........

[ARCHIVED THREAD] - How to identify which pattern bcg

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