BCM Blem Upper Receiver Is In Stock

[montana]

[I wonder if they scratch them on purpose to make people feel like they're getting a good deal.



One man's out of spec receiver is another man's gold

A little mar on the anodizing is hardly out of spec, in fact I put on a little aluminum black and oil and it basically disappears. The BCM barrel and BCG channel is one of the tightest and truest I have seen. So much so, I won't coat it with Cerakote micro slick, it is that tight of a tolerance..

[StoneHendge]

A little mar on the anodizing is hardly out of spec, in fact I put on a little aluminum black and oil and it basically disappears. The BCM barrel and BCG channel is one of the tightest and truest I have seen. So much so, I won't coat it with Cerakote micro slick, it is that tight of a tolerance..

The inside diameter of the receiver extension is undersized. I.e., out of spec. They say so on their website.

[montana]

The inside diameter of the receiver extension is undersized. I.e., out of spec. They say so on their website.

Here is what is stated: Inside Diameter for barrel extension slightly undersized for a tighter fit to the barrel and a more accurate rifle. Please use a heat gun or hair dryer to warm up threaded bore of receiver if barrel extension is too tight.) The BCG channel is also smaller for a tighter and straighter fit..

So in your assessment, "a part that is highly manufactured to perform better" is out of spec if it doesn't meet the sloppy fit of +- mil spec TDP. OK, I'll give that to you. JP parts are also out of spec.

I just want others to understand it is better than mil spec, not a gimmick or for cultist as you have ascertained...

Carry on...

[DCC83501]

I'm a fan. I like the barrel thermo-fit feature.

Absolutely only upper I will use because of that specific feature.

[StoneHendge]

Here is what is stated: Inside Diameter for barrel extension slightly undersized for a tighter fit to the barrel and a more accurate rifle. Please use a heat gun or hair dryer to warm up threaded bore of receiver if barrel extension is too tight.) The BCG channel is also smaller for a tighter and straighter fit..

So in your assessment, "a part that is highly manufactured to perform better" is out of spec if it doesn't meet the sloppy fit of +- mil spec TDP. OK, I'll give that to you. JP parts are also out of spec.

I just want others to understand it is better than mil spec, not a gimmick or for cultist as you have ascertained...

Carry on...

BCM receivers aren't "more highly manufactured", they are manufactured no different than any other plus grade forged receiver, except that the receiver extension has a smaller ID. And yes, JP upper receivers do also have an out of spec receiver extension. And John Paul will be the first tell you (as he's told me) that you need to be extremely careful with the barrel extension that you put in it.

[montana]

Barrel extension OD can vary dependent on barrel manufacturer, but reputable manufacturers keep them within tolerances that pose zero problems with BCM thermal fit uppers. The BCM receivers I have used have been spot on. Anderson and Aero uppers have not held the same consistency as my BCM upper receivers. The Aero and Anderson upper BCG channel has also varied quite a bit as other brands compared to BCM. When QC is consistent, "then yes"BCM is a higher quality of manufacturing..There is an advantage to thermal fit barrels, "but if you doubt this" then you can explain it to John Paul the next time you talk to him...



There is a reason I use certain brand parts, and avoid others..Religion has nothing to do with it....

[StoneHendge]

Montana, I agree with you that McGowen shouldn't be considered a reputable manufacturer, but the fact I couldn't remove one of their barrels from a BCM receiver with a blowtorch and a mallet was the least of my worries given the other issues it had. Whether the issue with my inability to remove it was the receiver or the barrel extension (or a combination of both), only the dumpster and Eagle County landfill know.

But the potential pitfalls I otherwise see in the concept aren't related to the barrel extensions OD. A rack barrel extension goes for $20-25. When JP sold AR-15 barrel extensions ala carte, they were $60. There's a reason for that, and it's all about the exacting precision with which it mates with their receivers - in terms of alignment, not just dimension. In addition to only using a JP barrel extension, John Paul would also recommend only using a JP handguard since they also control the precision with which the barrel nut mates with the receiver extension, it's threads, and the flange on the barrel extension.

As to my comment about them being a cult, I was referring to the non-religous meaning. I think you (along with the few posters who have stated that they are the only uppers they'll use) have validated that. Along with my comment that one man's out of spec receiver is another man's gold. It is just an out of spec receiver to me .

[montana]

Montana, I agree with you that McGowen shouldn't be considered a reputable manufacturer, but the fact I couldn't remove one of their barrels from a BCM receiver with a blowtorch and a mallet was the least of my worries given the other issues it had. Whether the issue with my inability to remove it was the receiver or the barrel extension (or a combination of both), only the dumpster and Eagle County landfill know.

But the potential pitfalls I otherwise see in the concept aren't related to the barrel extensions OD. A rack barrel extension goes for $20-25. When JP sold AR-15 barrel extensions ala carte, they were $60. There's a reason for that, and it's all about the exacting precision with which it mates with their receivers - in terms of alignment, not just dimension. In addition to only using a JP barrel extension, John Paul would also recommend only using a JP handguard since they also control the precision with which the barrel nut mates with the receiver extension, it's threads, and the flange on the barrel extension.

As to my comment about them being a cult, I was referring to the non-religous meaning. I think you (along with the few posters who have stated that they are the only uppers they'll use) have validated that. Along with my comment that one man's out of spec receiver is another man's gold. It is just an out of spec receiver to me .

I have never had to destroy a receiver to remove a barrel, including from a BCM upper receiver. Here is a tool that would have prevented your upper's destruction.https://www.dwilsonmfg.com/Barrel-pr...ure_p_102.html It works very well..https://www.youtube.com/watch?v=abxYM6ZQK_E

I never once stated BCM uppers are the only uppers I will use. In fact I use Aero or Anderson when I want a Cerakoted rifle, especially when I use micro slick.. Stacking tolerances can be a problem when using different manufacturers products, no matter how good the quality is. This is where knowledge and experience comes into play.. An upper in spec may not fit a lower in spec from a different manufacturer. It doesn't mean they can't be fitted and used.. Hand guards, barrels, fire control groups, BCG's, buffer types, gas tubes, muzzle devices and even detents differ from manufacturer to manufacturer.

Mistakes are how we learn and believe me, I have made many through the decades.. I'm still learning...

Here is one of my builds. https://www.thefirearmblog.com/blog/...-now-you-dont/

[DCC83501]

Montana, I agree with you that McGowen shouldn't be considered a reputable manufacturer, but the fact I couldn't remove one of their barrels from a BCM receiver with a blowtorch and a mallet was the least of my worries given the other issues it had. Whether the issue with my inability to remove it was the receiver or the barrel extension (or a combination of both), only the dumpster and Eagle County landfill know.

But the potential pitfalls I otherwise see in the concept aren't related to the barrel extensions OD. A rack barrel extension goes for $20-25. When JP sold AR-15 barrel extensions ala carte, they were $60. There's a reason for that, and it's all about the exacting precision with which it mates with their receivers - in terms of alignment, not just dimension. In addition to only using a JP barrel extension, John Paul would also recommend only using a JP handguard since they also control the precision with which the barrel nut mates with the receiver extension, it's threads, and the flange on the barrel extension.

As to my comment about them being a cult, I was referring to the non-religous meaning. I think you (along with the few posters who have stated that they are the only uppers they'll use) have validated that. Along with my comment that one man's out of spec receiver is another man's gold. It is just an out of spec receiver to me .

Someone is full of themselves I see. Always interesting to see how some people enjoy the thought of looking down on others, and their experiences....................................... ...

[lazyengineer]

It is just an out of spec receiver to me .

Eh, to each their own. I run "out of spec" twist rates and "out of spec" barrel profiles too.

[keystone183]

Eh, to each their own. I run "out of spec" twist rates and "out of spec" barrel profiles too.

Somebody remind me of what 'mil spec' acceptable MOA is........

[Old Bob]

Somebody remind me of what 'mil spec' acceptable MOA is........

Mil-spec accuracy with iron sights for M16 rifles & M4 Carbines is around 4 MOA (4.5" for M16s & 5" for M4s at 100yds). I don't know if this is with M193 or M109 (M855) ammo. I've not seen a mil-spec for optically sighted rifles or carbines.

[StoneHendge]

Montana, I think we can agree to disagree! (btw, the shipped cost of that removal rod ($59 to me) is about what I paid for the BCM receiver ( I think it was $69)).

Someone is full of themselves I see. Always interesting to see how some people enjoy the thought of looking down on others, and their experiences....................................... ...

Please refrain from making personal attacks - it's a violation of Forum rules. I'm interested in hearing about how I'm looking down on anyone, though.

[montana]

Montana, I think we can agree to disagree! (btw, the shipped cost of that removal rod ($59 to me) is about what I paid for the BCM receiver ( I think it was $69)).

I'm sure an old barrel nut and 1" wood dowel could have worked just as well or better than beating on it with a mallet...Just saying.....

[StoneHendge]

I'm sure an old barrel nut and 1" wood dowel could have worked just as well or better than beating on it with a mallet...Just saying.....

I beat on a 1" wood dowel with the mallet. After heating the receiver extension with a blow torch.