Gunsmithing question-back of projectile exposed/not jacketed

[thejim2]

I bought some cheap 62 gr projectiles from MidwayUSA. The bullet is 90% jacketed, but the very rear/flat of the projectile is not jacketed/exposed (lead?). If firing this though an AR-15, can the exposed lead cause any issues down the road, IE excessive/damaging lead builup in the barrel/gas tube/bolt carrier key.

Thanks for any help.

 

[bohem]

Re: question-back of projectile exposed/not jacketed

Bulk grade FMJ's in 55 and 62gr this is common. I've never had an issue nor have friends of mine that use these type of cheapies and amongst a half dozen or so of us there are more than 40k of these sent downrange annually (two of my friends are especially trigger happy).