Hydro forming

[hodi]

Is it impossible to hydroform the IMI brass? I understand the whole value of my time thing, but I have more time than $ lately. I hadn't considered selling the brass. I'm not really sure where to even do that. Midway is selling Winchester for $399/1000, so I could probably price a little below that & make someone happy if we could get together. It's been my experience that most forums don't allow you to sell until you have been a member/posted for a while, so I couldn't just go to AR15.com & post. I might be willing to sell my brass, but I'm not completely convinced that hydroforming it isn't the way to go. Keep the responses coming. I'm really appreciating your perspectives.

[txgunner00]

My experience with hydroforming IMI brass is I had to wack the snot out if the ram but still didn't get complete form. It could still be used but it wouldn't be fully formed until after the first firing.

[hodi]

I'm going to South Dakota in August for a prairie dog hunt. I'd like to try my Grendel at some distance. I'm not confident I could sell my IMI brass in time to do me any good for that trip. If hydroforming is impractical, does fireforming make sense? I've heard it said that the fireforming loads can be decent. What would be a good load, and does anybody know where I could find any inexpensive projectiles? I'm not interested in the "Cream of Wheat" method. I did read where somebody used delrin as the bullet. I think he said he shot into a pillow, of all things! That would work just fine for me if I could find delrin that could be cut down properly. Surely that would be less expensive than $23.99 for Hornady A-Max @ Midway. If the fireforming loads were good ones, I guess I wouldn't mind using them for p-dogs.

[hodi]

I just had a thought. Would wax work for a fireforming projectile? Fast draw cowboys use it with light loads. That might be something that was inexpensive enough to use that the cost would really just be in the power/primer. If this would work, does anyone have any recommendations for powders & light loads? I understand any loads are only safe in your guns, liability, blah, blah, blah...I would then just have to work out my cookie cutter method for loading them. I'm still interested in using regular fireforming loads if they have a rep as good loads.

[badgerlb]

ive fire formed with 2 moa accuracy with the speer hot cor 120's... they're not spectacular... but you could hunt with them.

[txgunner00]

I've gotten pretty decent results from 100 NBT's out of non fire formed 7.62 x 39 brass. 26.5 gr of IMR 8208 (compressed load) gave me 3/4" MOA @ 2507 fps. So far all my loads for the 100 NBTs have also worked well with 100 Amaxes.

For comparison, the load for same bullets in FF cases is 28.7 gr of IMI 8208, 2700 fps & 3/4" MOA.

[StoneTower]

You can sell unloaded brass on craigslist. Try and sell it and if it doesn't work, you haven't lost much because it is free to try. My problem with forming brass is that it costs almost the same by the time you get the brass and consume the primers, powder and bullets. The final product does not have the exact same capacity as actual Grendel brass and it does not last as long as actual Grendel brass. The Grendle is a great caliber for the AR15, but it is on the edge of anemic and having even less powder capacity in the final formed brass does not make me excited.

Is it impossible to hydroform the IMI brass? I understand the whole value of my time thing, but I have more time than $ lately. I hadn't considered selling the brass. I'm not really sure where to even do that. Midway is selling Winchester for $399/1000, so I could probably price a little below that & make someone happy if we could get together. It's been my experience that most forums don't allow you to sell until you have been a member/posted for a while, so I couldn't just go to AR15.com & post. I might be willing to sell my brass, but I'm not completely convinced that hydroforming it isn't the way to go. Keep the responses coming. I'm really appreciating your perspectives.

[pinzgauer]

My problem with forming brass is that it costs almost the same by the time you get the brass and consume the primers, powder and bullets.

I agree it does not make sense to buy 7.62x39 brass *now* to try to reload with the reduced cost of Hornady brass. But when the IMI deals were available, and proper grendel brass was not, fireforming worked great. The difference is you are assuming the fireforming load is a waste. I fireformed with 100g loads which shot to same POI as the full power 120g, and they were very accurate

The final product does not have the exact same capacity as actual Grendel brass and it does not last as long as actual Grendel brass. The Grendle is a great caliber for the AR15, but it is on the edge of anemic and having even less powder capacity in the final formed brass does not make me excited.

You are assuming reduced case capacity results in 1:1 reduction in velocity... that's not the case most of us saw with IMI. Reduced powder required, but not an equivalent percentage reduction in velocity. I think LR1995 was the first to figure this out.

I'm seeing 7-8 reloads on IMI before the primer pockets get loose. Occasional neck splits around that timeframe, but usually it's a stress crack from where the neck was scratched. Depending on how you are gassed, the brass is getting pretty beat up around that timeframe anyway, so I'm OK with that.

If starting new, I agree, fireforming is not the way to go. If I had a ready supply of inexpensive IMI 7.62x39, I'd sure use it! I'd also considering buying virgin IMI if the price was right.

[hodi]

Pinzgauer, your response is encouraging. Since I have 1000 rounds of the IMI, that would be a lot of shooting. Where do you recommend starting with a fireforming load with the 100gr A-Max. Hodgdon's sight shows regular starting loads for the 95gr V-Max and also Nosler's 100grBT @ 28gr of H335, so I imagine the A-Max data would be similar. What powder/load starting point would you recommend, allowing that you have no liability for my reloading techniques? Also, what would you consider a good price for 1000 virgin IMI 7.62x39?...

[StoneTower]

The lack of brass at a reasonable price was the very reason I started with Winchester 7.62x39 brass. When I got into the Grendel I could not justify $1.05 for empty brass from Midway when that was all there was to be had. I liked the idea (and still like the idea for some calibers) of hydro forming as it saves primers, powder, bullets and barrel life but it takes time. I don't get to shoot as much as some and have to drive 30 miles each was to go to the range. When I go hunting, I want 100% of what the Grendel has to offer and if I lose a case or two that is a small cost in an otherwise expensive sport. Some guys shoot hogs and are lucky enough to have many targets and the cost in that satiation might make a difference. For shooting targets, brass that lasts 15-18 reloads is probably more cost effective than brass that lasts 3-5.

I agree it does not make sense to buy 7.62x39 brass *now* to try to reload with the reduced cost of Hornady brass. But when the IMI deals were available, and proper grendel brass was not, fireforming worked great. The difference is you are assuming the fireforming load is a waste. I fireformed with 100g loads which shot to same POI as the full power 120g, and they were very accurate.

[hodi]

My South Dakota trip got moved up to this Friday (6/8). I'm still considering trying to maybe fireform 100 or 200 rounds to take with me. I'm seriously considering trying to use patches (no cream of wheat). Otherwise, I may just try to take some fireforming loads with me using standard bullets. If I use a patch to plug the case necks, can I just leave the gas tube alone? It seems like I should be able to. On further reflection, the wax bullet idea was probably lousy, as wax would probably end up in the gas tube. Anyway, further advice is very welcome.

[txgunner00]

I would close off the gas port if you are using anything other than a bullet. The risk of a rupture in the gas system is not worth the few minutes it would take to rotate the gas block.

[hodi]

I am ashamed to admit that I don't really know how to do that.

[hodi]

txgunner00, do you mean drive the pins out & pull the gas block loose & rotate it? I would assume you would have to pull it forward off of the gas tube to do this. Is that correct?

[StoneTower]

Some guys have clamp on style gas blocks. Not the ones with a set screw but the ones that actually clamp on the barrel. You just rotate it. You could use a second gas block that has the gas tube hole plugged.