Front bag hardness

[magic mike]

OK guys and gals I need some solid input from you bench shooters. As I am new to the precision shooting game I have much to learn so I am looking for some guidance based on experience.

S&S built .308, Brux 1-10T Rem varmint contour, 25", Trued Rem action, bedded. Highly modified HS stock.

Front bag is a Protektor with the slick silver material on it.

My question is; If, after tightening my grip and pulling my rifle harder into my shoulder, my groups tighten dramatically is this an indication of the front bag being to hard? The gun has a 3" wide, flat forearm and a flat parallel butt stock. The front bag is a flat bottom bag made to fit 3" wide forearms. It appears that when I get down harder on the gun it also took care of the occasional flyer.

Any guidance would be greatly appreciated.

 

[Shynloco]

Magic,
I've tried a number of different combinations or both hardness and the material on my front rest bags. I believe what you are looking for REGARDLESS of the rifle or stock you are using, is a nice smooth sliding action and the front and rear bag working in concert with one another. Looking at the front bags, I have my center bag quite hard and the side bags (adjustable windage top) not quite as hard, but hard enough where they don't impede the sliding OR create drag. Don't know if you are aware, but many of the top competitors now use a material known as "Super Slick." Protektor bags actually come with this material on them (specific bags or they can make you a custom one) and that helps to make a nice smooth slide. Absent that material, consider using baby powder on it if your bag is a one piece bag made of leather or that clothe stuff. Or consider applying Carnuba car wax of the bottom of your stock to enhance a slicker slide. But also make sure your rear bag is not impeding what you've accomplished with you front bag. My move to that Super Slick material has helped me obtain that nice free sliding movement across all my bags and the change has helped improve my results downrange.

Alex

 

[Lapua40X]

IMO, the front bag, while it helps to guide the fore-stock and support it in the desired position, is essentially a skid surface. It doesn't "hold" anything. If it's very hard the rifle will react differently than if it is very soft. But unless, while your increasing should contact you are also pressing the rifle harder into the bag surface, the shoulder pressure shouldn't affect the rifle's relationship with the front bag. A soft bag should produce less "bounce" in the fore-end because it absorbs more of the rifle's energy at that point than we might expect from a hard bag. When you change shoulder contact with the butt of the rifle and tighten your grip you introduce new dynamics to the entire recoil experience. In this case, at least two new dynamics. Taken to the extreme, "free recoil" says the rifle gets to do whatever it wants when the shot is fired. If we're not careful, tightening the grip on the rifle may introduce subtle rotational forces on the stock; and it changes your trigger pull. Pulling the rifle with greater firmness into the shoulder will affect the overall dynamics of the rifle under recoil (when the rifle comes back against your firm shoulder contact it has less freedom to move to the rear) depending on how much shoulder pressure you exert.
Back in the days when I worked with moving objects that struck immovabie objects I was fascinated with the way energy moved; action/reaction. Take a look at this image:
http://www.wantchinatimes.com/newsphoto/2012-06-10/450/C414X0441H_2010%E8%B3%87%E6%96%99%E7%85%A7%E7%89%87_N71_copy1.jpg
Imagine the wall as your shoulder and the rear bumper of the car as the muzzle of your rifle. The muzzle moves toward the path of least resistance.
When the change in the way you manage your rifle is positive, don't over think it by wondering about your equipment. Enjoy the experience, remember that what you did today worked and that you can expect it to work tomorrow.

 

[LHSmith]

It appears you have found how your rifle likes to be driven. A hard front bag can cause vertical. Just make sure to "massage" the front bag periodically to prevent it from getting a rock hard set....and don't use those blocks they sell to place inside the bag when not in use claiming it "keeps the bags form".
Don't know what front bag you use, but on Cordura I tried various silicone sprays, Sinclairs bag wax, and even powdered teflon, and I ended up with a very grabby bag. Now i simply brush the bag with a nylon brush after every outing. YMMV
If it's tracking well, your good to go. If not experiment with more or less sand.

 

[Patch700]

How much have you played with rear bag position and also how much fore end you hang off the front rest...

I see that you said it's a .308 and you made no mention of a brake of any kind , assuming it is balanced well if it came from S&S but perhaps it could only be balanced to a point if there were weight restrictions to conform to.

I have a couple F class stocks that just simply will not track very well when free recoiled with calibers such as 6.5x284 , they needed a bit of hold and they smartened rite up... They were also very sensitive to positioning in the bags until I added weight to the butt stock.

If your gut is telling you it may be slightly nose heavy you might try moving the front rest rite to the very end of the fore end and see how it reacts.


Good luck.