No manufacturers recommend using reloaded ammo. That is true for ALL guns and barrels.
I would highly recommend a Storm Lake conversion barrel. These are quality stainless steel barrels with fully supported chambers made right here in the USA, and you can get them at reasonable pricing. For example, Midway sells them for only $135
For converting Glock 27 to 9mm:
http://www.midwayusa.com/viewProduct...tNumber=935826
For converting Glock 27 to .357 Sig:
http://www.midwayusa.com/viewProduct...tNumber=686704
You can also order custom barrel lengths, and porting or threading options if you order direct from Storm Lake. Here is a link to their website:
http://www.stormlakebarrel.com/barrels
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