Question about BCG swap

[number9xd]

Got a question for you guys. I have a Double Star rifle that I have only put 20rds through (I know, gonna resolve that SOON). The rifle had a 4140, 1/9 upper on it from factory. I recently swapped that upper out for a J&T/Double Star 4150, 1x7, M4, "F"-fsb upper. I plan to use the original BCG with this upper. I would think that will not be an issue with only 20rds, is that correct?

Here's the next part to this question. I also have a complete build with BCM middy upper. I picked up 3 RRA BCG's a few months ago to ensure I had some. I plan to jump on the LMT F/A BCG when they get in stock at Bravo. When I get them, I will use them in the guns with the BCM middies and either keep the RRA BCG's as backups or sell them and replace with LMT backups when the next round comes in stock. However, having this BCM middy laying here is itching my finger wanting to shoot it. I plan to go shooting this weekend. Would there be any harm in sticking the Double Star BCG mentioned above in the BCM to run a few rounds (25 or so) through it just to get my fix?

***ETA - I do not have a headspace gauge at this time. Is it really a must to get a gauge and check HS on a new BCG and upper before firing?

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[mmike87]

I'm not always clear on the headspace issues either. I THOUGHT that you were generally always OK to use a new bolt in a rifle, but headspace checking was really important when placing a used bolt in a different rifle. If you only have a few rounds in the doubelstar - I doubt that qualifies as "used."

For example, I bought a new BCM FA BCG to upgrade a RRA rifle with apx. 1000 or so rounds on it and was told that was fine - and so far it works great.

I may be wrong though - but I thought I read that here.

But a headspace gauge is certainly a good idea then you can just always check and not worry about it.

[number9xd]

Thanks for taking the time. I'll just shoot as planned. I couldn't imagine it would not be okay, just wanted to get some confirmation from those who have been there done that.

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