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can we discuss blowback?

Posted: 20 Nov 2020 21:37
by stevep1954
a fellow lever lover was mentioning blowback when using the 45 colt in his Rossi. does it happen on just levers and why? i am not even sure what it is... thanks

Re: can we discuss blowback?

Posted: 21 Nov 2020 03:26
by Archer
Blowback is a term I have not heard applied to lever actions.

I am going to make an assumption here that 'blowback' in this case is referring to combustion gases escaping past the brass and coming toward the shooter.
It is possible that a lightly loaded round may not expand the brass enough to form a gas seal in ANY firearm.

I have NOT experienced this with ANY of my lever actions and I probably own a dozen.
I do not however own a .45 Colt and I do not as a rule run light loads through the lever actions.

.45 Colt is a round that is often loaded quite lightly for Cowboy Action or other light plinking. .45 Colt brass is available today in a thicker hardened brass that can be used for magnum level loads and may require annealing for use with light .45 Colt loads. Failure to anneal the brass while using it for light loads may not give you the proper gas seal. The Rossi chambers are sometimes a bit generous and combined with a light load common with .45 Colt might not give you the gas seal you would want. Combine all these factors and you are more likely to have a problem.

I did do a search on the topic with specific reference to the Rossi 92 and I got this thread off another board:
https://www.thehighroad.org/index.php?t ... es.485157/
(I will note with regards to the end of the conversation that while names may be trademarked patents are specifically not applicable to dimensions alone at least in today's world. Something that came out in the ParaOrd wide body 1911 patent case. I will also note that .44-40 was potentially loaded a bit hotter than .45 Colt and that there was specifically a 1892 ONLY loading available from Winchester.)

Re: can we discuss blowback?

Posted: 21 Nov 2020 11:32
by Ohio3Wheels
I have found during load development for my 45 Colt '92 that the low starting loads often result in smokey cases and some powders Titegroup in particular never seem to develop sufficient case expansion to totally seal the chamber before reaching maximum load. As Archer noted some or all of this may be related to case metallurgy.

Make smoke,

Re: can we discuss blowback?

Posted: 21 Nov 2020 20:10
by Missionary
Yep.... those minimal charge loads and cases sized to small for a fat chamber will permit gas escape along the brass back towards the bolt.
Cowboy shooters looking for the Edge fire loads that are so low powered a turtle an near out run them.
What purpose those loads have is beyond me.
But you can anneal the neck area of the brass if you want to at sneeze your slugs down range.

Re: can we discuss blowback?

Posted: 22 Nov 2020 07:54
by GasGuzzler
Missionary wrote:Cowboy shooters looking for the Edge fire loads that are so low powered a turtle an near out run them.
What purpose those loads have is beyond me.
Same here. I bought some .45 Colt brass from a local guy and he tried to pawn some Trail Boss off on me. :lol: