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Mcliff1971
09-02-2018, 01:37 PM
Happy Sunday everyone!

Quick question about testing hardness of recently cast bullets. Is there a minimum amount of time you should wait before testing hardness (Lee hardness tester) to get a more accurate reading?

Thanks in advance!

Mike

ukrifleman
09-02-2018, 01:54 PM
Although some say 48 hours is enough, I leave mine for a week before testing.

ukrifleman

Grmps
09-02-2018, 02:09 PM
↑☻↑☻↑↑↑☻↑☻↑

Mcliff1971
09-02-2018, 02:11 PM
Thanks! Appreciate the quick response!

Larry Gibson
09-02-2018, 03:53 PM
If WQ'd or otherwise HT'd I wait 48 hours. With AC'd bullets I prefer to wait 2 weeks (14 days) but find that with some alloys 7 - 10 days is sufficient.

Mcliff1971
09-02-2018, 05:25 PM
If WQ'd or otherwise HT'd I wait 48 hours. With AC'd bullets I prefer to wait 2 weeks (14 days) but find that with some alloys 7 - 10 days is sufficient.

Larry - does powder coating them fall into the heat treated catagory?

Larry Gibson
09-02-2018, 10:22 PM
I will leave that to those who PC. However,if the PCd bullets are WQd after. Aking them I suspect some degree of HT takes place.

RobS
09-03-2018, 12:04 AM
Powder coating or Hi-Tek coating would be the same as air cooling a bullet if left to air cool. If a person is water dropping then you will yield the typical hardness from water dropping at 400 degrees from the antimony alloy you are using. 400 degrees is the typical curing temperature of powder coating or Hi-Tek and normally for 10 to 15 minutes so that is also something to consider if water dropping and is why boolits don't have the increase in hardness vs the higher temps. My experiences with water dropping wheel weight alloy by means of Hi-Tek resulted in a bullet just a slight bit harder than air cooled unless I jacked the temps up which then jeopardized the coating (would flake off on smash test).

JonB_in_Glencoe
09-03-2018, 12:25 AM
that time varies with different alloys...a safe answer is usually 2 weeks, but you may notice slight hardness changes out to 6 months if there is some Cu in the alloy.

If you have a large batch of a certain alloy you want to know about, I'd suggest testing some boolits daily for three weeks (starting 1 hour after cast) ...maybe even a few more tests after that, out to 6 months.

Mcliff1971
09-03-2018, 10:48 AM
that time varies with different alloys...a safe answer is usually 2 weeks, but you may notice slight hardness changes out to 6 months if there is some Cu in the alloy.

If you have a large batch of a certain alloy you want to know about, I'd suggest testing some boolits daily for three weeks (starting 1 hour after cast) ...maybe even a few more tests after that, out to 6 months.

Sounds good. Thanks again everyone!