Load issues (blowback) 454 Casull

Hey, looking for advise.

Current load:
454 casull in Rossi 14” barrel
Hornady brass (not annealed)
250gr RNFP
Win 296 - 28.5gr (max load)
Small Rifle Primers

I’ve run some light loads in this rifle using AP70N, which works fine. These loads with the Win296 is giving me issues. Getting a lot of blowback, which is visible on the cases (soot marks). It’s almost like the powder is not burning quick enough and therefor not expanding the cases fast enough, and therefore causing the blowback. Results are the same with older Winchester Brass.
Don’t have a chrono to check velocity, but shoots an okay group at 100m with red dot sight.

I’ve read on other forums that W296 and H110 needs a magnum primer for better ignition. Others claim switching to Lil’ Gun yielded better results.

Anyone know what I should try?

Max load getting blowback? Sounds a bit odd. I would just change powder and see how that goes.

Sent from my SM-T510 using Tapatalk

memory bank trying to remember what it is about 296......something funny about it.....magnum primer could well be worth a crack.

Would that be a Small Rifle Magnum or Small Pistol Magnum primer?

lil gun may be faster velocity...but with hunk of lead that big how fast do you really want????
tray of small rifle magnum primers is stuff all $$$ to outlay and may fix issue...maybe...sounds weird you getting low pressure signs with top weight load....very weird.light crimp may be another thing to try....might hold things together tiny bit longer allowing better burn.
how does rifle go with factory load???

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Originally Posted by Micky Duck

lil gun may be faster velocity...but with hunk of lead that big how fast do you really want????
tray of small rifle magnum primers is stuff all $$$ to outlay and may fix issue...maybe...sounds weird you getting low pressure signs with top weight load....very weird.light crimp may be another thing to try....might hold things together tiny bit longer allowing better burn.
how does rifle go with factory load???

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Not too bothered with super fast velocities - just not sure it’s doing what the load data says.

Crimp is as tight as It can be I think, without putting dent in bullet.

Factory loads (Winchester SuperX 250Gr) worked fine. Have not tried since chopping barrel tho.

Ball powders evidently do benefit from magnum primers. If you are getting in complete burn there should be residue visible in the bore.

go hunting (take the 243 ) clear your head and think about it while you sit at camp wishing you had the 454 with the red dot when you were pushing thru the shitty bush and a silly spiker disappeared before you could close the bolt.........when you get home lock yourself in the reloading shed and try what these guys have mentioned above.....

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Originally Posted by thatguy

Hey, looking for advise.

Current load:
454 casull in Rossi 14” barrel
Hornady brass (not annealed)
250gr RNFP
Win 296 - 28.5gr (max load)
Small Rifle Primers

I’ve run some light loads in this rifle using AP70N, which works fine. These loads with the Win296 is giving me issues. Getting a lot of blowback, which is visible on the cases (soot marks). It’s almost like the powder is not burning quick enough and therefor not expanding the cases fast enough, and therefore causing the blowback. Results are the same with older Winchester Brass.
Don’t have a chrono to check velocity, but shoots an okay group at 100m with red dot sight.

I’ve read on other forums that W296 and H110 needs a magnum primer for better ignition. Others claim switching to Lil’ Gun yielded better results.

Anyone know what I should try?

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Greetings,
From memory 296 should not be used in reduced loads and does need a hotter primer. The soot is due to pressures being too low. This can be dangerous. Will do a bit of digging.
Regards Grandpamac.

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Originally Posted by thatguy

Hey, looking for advise.

Current load:
454 casull in Rossi 14” barrel
Hornady brass (not annealed)
250gr RNFP
Win 296 - 28.5gr (max load)
Small Rifle Primers

I’ve run some light loads in this rifle using AP70N, which works fine. These loads with the Win296 is giving me issues. Getting a lot of blowback, which is visible on the cases (soot marks). It’s almost like the powder is not burning quick enough and therefor not expanding the cases fast enough, and therefore causing the blowback. Results are the same with older Winchester Brass.
Don’t have a chrono to check velocity, but shoots an okay group at 100m with red dot sight.

I’ve read on other forums that W296 and H110 needs a magnum primer for better ignition. Others claim switching to Lil’ Gun yielded better results.

Anyone know what I should try?

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Greetings Again,
Had a quick scratch around. I see that Hodgdon specifies Winchester small rifle primers. Ball powders like 296 are a bit hard to ignite and the Winchester primers are formulated for this. If you are using a non Winchester primer this could be your problem.
Regards Grandpamac.

Shortening the barrel may possibly have had an influence on this. I went back through my notebooks and used to reload for the m1 carbine about 20 years ago using 296 and 110 grain projectiles and see I ended up at 1 grain over book max comments for lighter loads were sooty, unburnt powder and for one fails to cycle. Primers were std small rifle.

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Originally Posted by grandpamac

Greetings Again,
Had a quick scratch around. I see that Hodgdon specifies Winchester small rifle primers. Ball powders like 296 are a bit hard to ignite and the Winchester primers are formulated for this. If you are using a non Winchester primer this could be your problem.
Regards Grandpamac.

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I’m at max load tho so not sure why too low, probably not ingiting.
Using Federal primers, could try Winchester as well as Magnum.

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Originally Posted by Marty Henry

Shortening the barrel may possibly have had an influence on this. I went back through my notebooks and used to reload for the m1 carbine about 20 years ago using 296 and 110 grain projectiles and see I ended up at 1 grain over book max comments for lighter loads were sooty, unburnt powder and for one fails to cycle. Primers were std small rifle.

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Interesting, I would have thought it won’t make much a difference since load data is for Pistol (9.3” barrel)

I had similar issue loading my 32-20 for a rifle. Dirty cases, very dirty powder residue in barrel indicating poor combustion. Using Vihtavuori though not 296.
Lee in his book says that crimping will fix that or at least give better combustion. Got a crimp die and it made no difference.
Tried magnum primers (pistol IIRC) even though the VV I am using is not a ball powder, and no change.
Velocities and accuracy were acceptable.
I mostly used jacketed projectiles but when I tried cast I think I used a rifle load rather than a pistol load out of the reloading manual.

In the end lived with the issue as my 32-20 is only a 50 yd fun gun.

You could though as suggested though try magnum primers, or change powder.

On the subject of Lil'gun. I never had much success with it but that was in my Hornets. Sure I got higher velocity for supposedly lower pressure but accuracy wasn't that great and ES was bad.

On the subject of magnum primers with ball powder. I use W760 in my 6.5 Ackley. I have fired 1000 round thru it and had one misfire and I believed that to be a faulty primer. Everyone harangued me with "You MUST use magnum primers with 760 ball powder. You will get a slightly higher velocity and more consistent ignition". Well, I tried magnum primers and my velocity hardly rose at all, my ES blew out, my long range accuracy fell off. Back to std BR2 primers and business as usual. Maybe in a larger capacity case I would have seen a benefit.

Thanks for the insights @zimmer. Not much harm in trying different primers and then powder. Shame I have to buy at least 1lb to try even though it may not work as with the 296..

hopefully you wont need to buy a whole lb.....I know gunworks were selling wee sample jars of powder for stuff all cost...think marmite 2" high and 1" fat.... bought trail boss that way twice,about 50 loads in wee jar LOL.
someone up your neighbourhood will have some to trade/sell/swap ask around and see.

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Originally Posted by Micky Duck

hopefully you wont need to buy a whole lb.....I know gunworks were selling wee sample jars of powder for stuff all cost...think marmite 2" high and 1" fat.... bought trail boss that way twice,about 50 loads in wee jar LOL.
someone up your neighbourhood will have some to trade/sell/swap ask around and see.

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Good point, maybe I’ll start a new thread and ask. Thanks

Greetings Thatguy,
I had a scratch through an old pile of Handloader magazines and turned up an article on the 454 in 1994. The Author made 2 recommendations. First not to reduce 296 loads below start loads. Second was to apply a very firm crimp to the hotter loads. He was using a Freedom Arms revolver so the crimp could have been to stop the projectiles moving forward and jamming the cylinder or it could have been to help the powder ignite properly or both. His loads were fire cracker hot for the freedom revolver and probably excessive in your much weaker Rossi so they will not be mentioned. So one thing that you could try, if you haven't already is a firm roll crimp. Zimmer mentioned this in his post although in his case it did not help. This will need a projectile with a crimp groove. Your seating or crimp die should be able to do this. I should point out that I have zero practical experience in loading pistol cartridges but am an insatiable reader of the Handloader articles.
Regards Grandpamac.

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Originally Posted by grandpamac

Greetings Thatguy,
I had a scratch through an old pile of Handloader magazines and turned up an article on the 454 in 1994. The Author made 2 recommendations. First not to reduce 296 loads below start loads. Second was to apply a very firm crimp to the hotter loads. He was using a Freedom Arms revolver so the crimp could have been to stop the projectiles moving forward and jamming the cylinder or it could have been to help the powder ignite properly or both. His loads were fire cracker hot for the freedom revolver and probably excessive in your much weaker Rossi so they will not be mentioned. So one thing that you could try, if you haven't already is a firm roll crimp. Zimmer mentioned this in his post although in his case it did not help. This will need a projectile with a crimp groove. Your seating or crimp die should be able to do this. I should point out that I have zero practical experience in loading pistol cartridges but am an insatiable reader of the Handloader articles.
Regards Grandpamac.

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Thanks again. I would need to change projectiles to one with a crimp groove as I’m unable to crimp mine anymore without damaging the brass and bullet.

In the meantime, I’m picking up some lil gun from another member to try. Will maybe circle back to 296 on another day with magnum primers, different projectile and heavier crimp.

As far as load was concerned, I was already at max 28.5gr.

@7mmwsm

Greetings yet again Thatguy,
A bit more fossicking turned up a couple of old Winchester reloading components pamphlets. The latter recommended the standard Winchester small rifle primer and referred to the following warning.

Warning For 296 Powder.
Loads using 296 powder require heavy bullet pull (heavy crimp). Using 296 powder with a light bullet pull (light crimp) may result in squib loads and cause damage to the firearm, shooter and or bystanders.

Winchester also does not give any starting loads for 296. Their max loads are also considerably higher than the current Hodgdon data. Lil gun may be a better option but you may still need a crimp for best results.
Regards Grandpamac.

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Originally Posted by grandpamac

Greetings yet again Thatguy,
A bit more fossicking turned up a couple of old Winchester reloading components pamphlets. The latter recommended the standard Winchester small rifle primer and referred to the following warning.

Warning For 296 Powder.
Loads using 296 powder require heavy bullet pull (heavy crimp). Using 296 powder with a light bullet pull (light crimp) may result in squib loads and cause damage to the firearm, shooter and or bystanders.

Winchester also does not give any starting loads for 296. Their max loads are also considerably higher than the current Hodgdon data. Lil gun may be a better option but you may still need a crimp for best results.
Regards Grandpamac.

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Thanks for confirming that. Wonder what sort of load they would recommend?

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Originally Posted by thatguy

Thanks for confirming that. Wonder what sort of load they would recommend?

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Google it. There's lots of info (use at your discretion). It's quite a minefield of info.

I did see one at 35.5 gr Lil'gun. Cannot remember projectile weight.

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Originally Posted by thatguy

Thanks for confirming that. Wonder what sort of load they would recommend?

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Greetings Again,
I am not sure what projectile you are using as you just say RNFP. The maximum load you quote is for the 250 grain Barnes X projectile. These are solid copper alloy and are very hard. This requires a considerable reduction in powder charge. If you are using a lead core projectile then you would be better to use the Hodgdon data for the 260 grain Freedom Arms projectile which gives a low load of 34 grains of 296. So if you are using a lead core projectile your loads are 5.5 grains under the minimum load. This is dangerous country and I suggest that if you have any unfired loads that you not fire them and pull the projectiles to make them safe.

If you go to Lil gun Hodgdon has loads that approach the 296 loads at much lower pressure. Your Rossi is a derivative of the Winchester 92 and may be marginal in strength compared to the revolver that the data was developed for so Lil gun may be your best choice. The start load for the lead cored 260 grain of 33.4 grains of Lil gun giving 1,744 fps in their test barrel would be a good place to start. This is more velocity than you are likely getting from your current load.
Feel free to ask any questions.
Grandpamac.

grandpamac......tell you something for nothing is case of similar size...trailboss gives HIGHER pressure than other powders for similar velocity...I checked the data four times and yip its still the same.
lil gun worked great for me in both the .410 and the 7.62x39mm

Hi all, tried some new loads on the weekend. Now Lil’Gun with 240gr Hornsby XTPs. With the lighter bullet I was able to load 35-38gr powder, which fills the case up. That did the trick and getting no more blowback, a lot more recoil suggesting proper ignition and case expansion.

3 shots touching out of 5 shot group, at 50yards (using red dot sight for tight bush hunting).
I’ll work on the loads a bit more but keen to see what these XTPs do at the 2000fps it should be going at.
Thanks @MSL for the powder and others for the advise.

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Originally Posted by thatguy

Hi all, tried some new loads on the weekend. Now Lil’Gun with 240gr Hornsby XTPs. With the lighter bullet I was able to load 35-38gr powder, which fills the case up. That did the trick and getting no more blowback, a lot more recoil suggesting proper ignition and case expansion.

3 shots touching out of 5 shot group, at 50yards (using red dot sight for tight bush hunting).
I’ll work on the loads a bit more but keen to see what these XTPs do at the 2000fps it should be going at.
Thanks @MSL for the powder and others for the advise.

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*Hornady XTPs

@grandpamac, something interesting I just observed from Hodgdon website, which is what I use for data.

For Winchester 296 you can load:
36-38.2gr - with 240gr bullet.
26-28gr - with 250gr bullet.
34-36gr - with 260gr bullet.

I find it strange that the load is so light with a 250gr bullet, but then jumps up again with 260gr bullet. Is it a typo? What does your reloading data say for a 250gr bullet?

I wonder if this is why I had issue - being way under charge....

Sooting of cases is common if you are using a suppressor and nothing to worry about. I have found Winchester ball powders to be very clean burning generally in non-suppressed firearms.

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Originally Posted by thatguy

@grandpamac, something interesting I just observed from Hodgdon website, which is what I use for data.

For Winchester 296 you can load:
36-38.2gr - with 240gr bullet.
26-28gr - with 250gr bullet.
34-36gr - with 260gr bullet.

I find it strange that the load is so light with a 250gr bullet, but then jumps up again with 260gr bullet. Is it a typo? What does your reloading data say for a 250gr bullet?

I wonder if this is why I had issue - being way under charge....

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Greetings Thatguy,
The reason for the low 250 grain load is the hard projectile that Hodgdon is using in their data. Winchester gave loads of 34 and 36 grains for a 260 grain jacketed soft point and suggested it not be reduced due the possibility of squib loads. The differences are solely due to the hardness of the projectile. If and only if your 250 grain projectile is a softer jacketed type like the JSP you can work up to the loads for the 260 grain. These days projectile of the same weight but different construction often need quite different loads. You might like to go back and re read my earlier posts.
Regards Grandpamac.

Just looking at grandpa macs comment reminded me that I had tried using up the 295 I had in several rifles with cast lead bullets. What a waste of time that was they were far too soft and slippery to get any pressure.