Accuracy Question, Freechex vs Hornady GC

[RCE1]

I am somewhat new to gaschecks, but have been casting and shooting for decades.

Most of my CB shooting has been BPCR competition, which I participated in successfully for a number of years. Business, home life changes and rising fuel costs curtailed my competition a few years back, but I have recently returned to casting with a few .30 cal rifle moulds and have been using gaschecks. I have several thousand Hornady checks in this caliber, but wanted to experiment with making my own aluminum checks. I bought a FreechexIII and a few rolls of Yonky's material. The output seems to fit well and the material is soft enough to work easily, but I have noticed the corners of the aluminum checks are noticeably more rounded than the corners of the ready made copper checks. I think I am using the Freechex setup properly and they seem to be very consistant in shape, fit and weight, but the rounded corners have given me pause. Theoretically, as long as the Freechex are consistant in fit, all should be fine, but the difference between the two types makes me wonder. Shooting cast bullets in general introduces a number of variables into the equation and variability in gaschecks adds yet another factor.

To those who have done more extensive testing than I have time for these days, have you noticed a measurable difference in accuracy between the copper checks from Hornady and the aluminum checks made as I have described above?

[Dthunter]

Speaking for myself, yes.

I find that when shooting my .308win at velocities below 2000 fps, I notice very little difference.

But as pressure increases,(2000 fps +), I notice the Aluminum gas check load groups just start to expand noticably.

Your milage may vary.

[Ed_Shot]

I recently did a comparison between Hornady and Frechex III in my 30-30 using both the 309-150-F and 309-113-F over 16.0 gr. of 2400. I saw zero difference between the two checks.

[williamwaco]

I recently did a comparison between Hornady and Frechex III in my 30-30 using both the 309-150-F and 309-113-F over 16.0 gr. of 2400. I saw zero difference between the two checks.


Ditto.

[Mugs]

The 2 groups in my avatar were shot with alum. cks. I can tell no diff. with Hornady cks. 100 yrds. with RCBS 200 sil. boolit. FWFL in gas ck. groove only.

Mugs

[Dthunter]

Just to add more info to my previous post:

My results are over more than 300 rounds of "direct" comparison.
AND, they are at/near top pressures used with the associated boolets/cartridge combo.

This is no small sample for sure. YMMV, but I "know" that my targets/loads/results are very consistant to my tests.
Most the tests were conducted in sub zero (Celcius)temps.
Then tested again in plus temps.
I was pleasantly suprised that there wasnt a huge difference in performance. Accuracy is "normally" better in warmer temps.

The tagets/groups are shot not only at 100 yards, but at 300yards as well. This gives me more information as to how/if the boolet remains stable after the 100 yard standard.
The accuracy suprised me a few times!

This cast boolet shooting is labour/time intensive! But very enjoyable.